Whistlespeak (episode)

While undercover in a pre-warp society, Captain Burnham is forced to consider breaking the Prime Directive when a local tradition threatens Tilly's life. Meanwhile, Culber tries to connect with Stamets, and Adira steps up when Rayner assigns them a position on the bridge.
== Summary ==
=== Teaser ===
Stamets runs a modified spectral analysis on the vial found with the clue onboard the , wondering if the scientists had designed these clues to mock you when you can't figure them out. The clue has been stalling the crew of the for two days, who have run hundreds of tests on it, only determining that the vial's composition is generic and the water within it is "pure, inert, distilled, and wet." Burnham suggests that since the vial is damaged, there might be a piece missing, while Tilly reports that the latest test shows it to just be distilled water once again. Burnham notes that the other clues had more to them such as words and symbols, but Stamets reports that the scans he reviewed from the Enterprise multiple times shows that there was never anything else there. Stamets tried fabricating the last two pieces of the map to see what would happen when he put them in, but nothing happened. There are no shortcuts on this treasure hunt, the crew must solve this clue in order to continue the search to find all five map pieces. Burnham suggests that since chemistry clearly isn't the solution, switching to history and anthropology and looking into planets where distilled water had cultural or symbolic significance 800 years ago, particularly ones that had severe droughts and would've needed rainwater alternatives.
Burnham beams into the Infinity Room where Dr. Kovich greets her. Burnham asks Kovich for their next coordinates, assuming that he brought her there as he has a lead on Moll and L'ak, but Kovich doesn't have anything yet. The is handling the search while Discoverys mission is to find the Progenitors' technology and they seem to have their hands full at the moment; Burnham admits that they're a bit stalled. Kovich states that the scientists who hid the technology each made their own piece of the clue trail in secret, meaning that they would've employed their respective fields of expertise in the process and as such, knowing the identity of the vial's creator might prove useful. Kovich pulls out a genuine 21st century legal pad on which he has written the scientists' names, having uncovered their identities. Simply calling himself resourceful when asked where he got his hands on such an archaic thing, Kovich sends Burnham back to her mission.
Culber speaks in Spanish with a hologram of his grandmother, asking her how to make their mofongo for his husband as Stamets can't remember the recipe. Culber's amused grandmother tells him that the mofongo they make is inedible so she would wait for Culber to take a nap to throw out what she made for him and replicate it instead. Laughing, Culber has Zora pause the program and instructs the AI to send a message to Dr. Pollard that they might be onto something with this grief-alleviation therapy using holographic replicas of lost loved ones. The hologram of his grandmother is exactly as Culber remembers her and Culber has Zora restart the program. Culber tells his grandmother that he shared his body with another on and ever since then, he has had a feeling that's hard to describe, and Culber wonders if his grandmother can help him to understand it. However, she can't so Culber has the computer check the database since his grandmother should be able to answer that, the two having spoken often about her spiritual feelings and practices. Culber's grandmother states that while that's true, she had also trained him to be a doctor, a man of science and how can they examine the soul when he has not yet examined the body. Culber is pleased with this answer and thanks his grandmother.
Burnham receives Kovich's list, which identifies the scientists as Doctors Jinaal Bix, a Trill, Carmen Cho, a , Marina Derex, a Betazoid, Hitoroshi Kreel, a Denobulan, and Vellek, a Romulan, with Jinaal, Cho, and Vellek all crossed out. The crew hasn't yet found clues from Derex or Kreel and Burnham is betting on Kreel being the one responsible for creating the vial, as Kreel's specialty was designing weather modification towers to generate rain. While Tilly guesses that they're going to Denobula, Stamets suddenly has an epiphany and verifies with Zora that Denobulan weather towers seed rain with silver iodide, which she confirms is typical of their function, both in the present and in Kreel's time. This means that the water should be filled with contaminants, but it's ultra-distilled. However, Burnham recalls that Kreel's file had mentioned that he did work in weather technology for other worlds and if a planet were arid enough, then water would have to be extracted from the air on a molecular level, meaning that there would be no contaminants. Zora reveals that there were fifteen M-class planets on Denobulan trade routes when the vial was created, but only one that was dry enough that water would need to be harvested in that particular way: Halem'no.
The Discovery spore jumps to Halem'no, which appears to be a desert planet with one massive section of green visible from orbit. Burnham reports to the bridge crew that long-range scans reveal a functioning weather tower of Denobulan design which manufactures rain and emits a low-grade force field that shields the planet's only habitable region from dust storms. The crew has been able to confirm that Doctor Kreel had designed the tower, so the next clue is most likely hidden inside of it. Commander Rayner wonders why Kreel would make a weather tower look like a mountain, which Burnham calls an excellent question and asks Adira, now manning a bridge station, about any life signs on the planet. Adira reports that there are humanoid life signs from a pre-warp, pre-industrial civilization. There's no functioning electrical grid and geological surveys show that the storms on the planet have gotten increasingly more severe over time. They suggest that Kreel might have installed the tower as a humanitarian mission and hid it so as not to violate the Prime Directive. Burnham applauds Adira's theory and is pleased to see them on the bridge, which Rayner explains is because they had requested more time up here and Rayner thought that they were ready. However, Adira is nervous about being on the bridge in the midst of the present situation.
Burnham warns that the Prime Directive will be a concern for Discovery too, meaning that they must get in and out without revealing their technological capabilities. Gallo reports that scans can't detect the clue inside of the tower as there is an unusual energy field surrounding it, one that keeps Gallo from beaming anyone inside of it as well. While Adira tries to figure out why, Burnham decides to head to the surface with Tilly to search for the clue before Moll and L'ak make their next move. Burnham has move the ship as close to the planet as she can without Discovery being seen and leaves Rayner the conn.
=== Act One ===
Dressed in native clothing, Burnham listens to a linguistics data analysis of Halem'nite whistlespeak as Tilly joins her. Burnham explains that the whistling is a component of the Halem'nite language, and she has Zora translate it into Federation Standard. Tilly wonders why the Halem'nites would speak in whistles, but Burnham explains that they don't always as the Halem'nites have a phonetic language for day-to-day interactions. However, the whistlespeak allows them to communicate across great distances, which isn't uncommon to find in cultures before communication technology evolves. A lot can be learned about a society by how individuals speak to one another. The Halem'nites lack any terms to denote societal status or class, have three distinct gender identities, prize connection with one another despite the hardships that they face, and they have multiple words for pain, injury, hurt, and dust. Burnham feels like she's back in Doctor T'Prasi's xenolinguistics seminar on Vulcan. Impressed, Tilly suggests that they could really use Burnham at Starfleet Academy and Burnham asks how her teaching job is going. However, the conversation is interrupted by Rayner with the news that they've loaded subcutaneous transponders into the transport system while Adira has been playing with Starfleet's latest retinal tricorder mod, which could come in handy if they need to be discreet. Burnham has herself and Tilly beamed to the planet near the tower.
On Halem'no, the two women activate their retinal tricorders and Tilly sarcastically wonders if Kreel could've picked a more gigantic place to hide the clue. Burnham guesses that the size of the place is why the Halem'nites call it the High Summit and they must've known it would be well-protected since the Halem'nites believe that they can commune with their gods there. Burnham asks Tilly about the academy and Tilly tells her that she just got a message from her student Cadet , who had served them drinks at the Millennium Celebration, something that Burnham remembers. Ross is thinking about leaving the academy to take a position on a cargo vessel, and she wants Tilly's opinion on whether or not she should do it. Tilly doesn't know what to tell Ross and she's not the first to want to go as they aren't giving the cadets what they need, but Tilly doesn't know what the problem is. Halem'nite whistlespeak surrounds them with the universal translator allowing Burnham and Tilly to understand it. The Halem'nites discuss traveling from afar and coming through the dust storms while others welcome them to the High Summit. A pleased Burnham notes that they all seem to be going to the same place.
On Discovery, Booker approaches Culber, asking if Culber can put him in touch with the ship's counselor on the Locherer. When the Locherer finds Moll and L'ak, Booker wants them to have a full background and know that they can use him as a resource for anything. Culber is sure that the Locherer has been briefed and he tells Booker that he needs to accept that there's just not anything that he can do right now. Culber encourages Booker to find something to distract himself, to find something that had occupied his brain in the past and focus on that so that Booker can recharge himself so that he's ready when he is needed. Booker asks if Culber ever gets tired of having all of the answers, and Culber promises to check in with him later.
In engineering, Stamets plays around with the map pieces and Culber asks for his husband's help to do a full neural scan on himself. Stamets is concerned, but Culber claims that they don't have a lot of data on the neurological aftereffects of zhian'tara and this is a chance for them to gather some. Concerned, Stamets asks if Culber is having some aftereffects, and he admits that he might be. Culber brushes off his husband's concerns, stating that they need this data and it's been awhile since they've gotten to work together. Stamets agrees to help him and Culber promises to prep everything, and they can start in the morning. The two kiss and Culber leaves, but Stamets doesn't appear to be fully convinced by his husband's dismissal of Stamets' concerns.
Burnham and Tilly find a group of Halem'nites heading for the High Summit. Anorah tells them that the group has been following the beacon voice since the moonrise and agrees to let the two Starfleet officers join them. Anorah breaks into a coughing fit, explaining that she had been clearing dust from an orchard and got lost in the Dry Lands. Anorah breathed dust for an entire night before the sun rose and her compeers could rescue her which Anorah guesses is why they tell elders not to take turns at the edge of the storms. However, if Anorah didn't clear the dust, someone else would need to take her place. Tilly lies that they came to worship at the High Summit and Anorah guesses that they came to pray for rain. The Halem'nites have been without it for too long and only the chosen devout may enter the summit. Burnham dismisses her confusion over this fact as being because she and Tilly are from far away in the east and they have never seen the High Summit before, but have longed to visit for years.
The compeers are greeted by Ravah who introduces themself as the voice that guided everyone to the High Summit. Anorah begins struggling to breathe again, and Ravah directs the group to take her to the Healing Grove quickly. As the others try to find Anorah's medicine, the two Starfleet officers are conflicted because Anorah's lungs are full of dust, but they could easily save her by dislodging the dust with a sonic percussion wave which would violate the Prime Directive. Burnham pounds on the woman's back, but rather than find Anorah's medicine, the compeers gather bowls and form a circle around the three. Banging on the bowls and rubbing their instruments around it in a circle, the Halem'nites create a sonic percussion wave that, combined with Burnham's pounding, dislodges the dust from Anorah's lungs, saving her life as well as causing the sand nearby to raise into the air. Overwhelmed by the noise, Burnham collapses.
When Burnham wakes up, Ohvahz apologizes, having not had time to warn Burnham of the intensity of the sound cure and Burnham is amazed that the Halem'nites found a cure at all. Tilly joins them with Ravah who has been telling Tilly all about the High Summit. Ravah explains that they too were born far away, but their father brought Ravah here after their mother died and Ohvahz became priest of the summit. Ohvahz wants to let Burnham regain her strength, but Ravah is excited because Burnham and Tilly were on the front lines, declaring that when their turn comes, Ravah will clear dust twice as fast as anyone else. Ohvahz reminds Ravah that the most important part is to work in harmony with your compeers which Ravah reluctantly concedes to. Burnham states that they're eager to enter the High Summit to give thanks to the gods, but Ohvahz tells her that the gods do not require an individual to enter the temple to give thanks.
However, Ravah, over their father's objections, states that they could get in if they want to by completing the Journey of the Mother Compeer. The Journey of the Mother Compeer is a race and a test of devotion because it's very grueling. Everyone says they are due because watching the race makes the gods happy and the Halem'nites have been without rain for so long. Only the person who wins the race is worthy of entering the temple. There, the winner is close to the gods and they can ask for their blessing. Ohvahz tries to dissuade his child, but Burnham states that they wish to share their devotion in whatever way they can. Ravah is excited as they can do it the next morning if Burnham and Tilly make the request, but Ohvahz is obviously less than thrilled about the idea. Burnham makes the request as nothing is more important to her and Tilly than entering that summit.
=== Act Two ===
The next morning, the compeers gather for the race and Ravah asks Burnham and Tilly if there's any message that they'd like for them to give to the gods when Ravah sees them. Ravah has been inspired to run, just as many others have been inspired by the two Starfleet officers as well. The difficulty of the Journey is legendary and most who undertake it don't even finish. Ohvahz attempts to dissuade Ravah from undertaking the Journey as they are too young, but Ravah refuses to listen to their father. Ravah is wearing their mother's bracelet to keep her close to them, and Ohvahz objects that he had promised their mother that he would protect Ravah, but they insist that they're devoted and can do this. Visibly unhappy, Ohvahz departs to begin the preparations and Tilly approaches Ravah, noting that she has a student, Ross, that reminds Tilly a lot of the young Halem'nite. Ross just wants to get out there and do as fast as she can. It can be hard even as a teacher to just step back, so Tilly can only just imagine what it would be like as a parent. Ravah's father is a great man, and Ravah just wants to show him that they can be great too. Burnham interrupts the conversation to pull Tilly aside.
Once alone, the two contact Discovery where Adira has done a historical regression of Halem'no's weather patterns, and the data indicated that there might've been other weather towers in the past. Discovery sent down a team of DOTs into the dust storm to check it out and they found four more towers across the planet. Over time, the other weather towers failed because their energy distribution matrices fell out of alignment and that's the same thing that's happening to the High Summit. It's also what's causing the energy field that's preventing Discovery from simply beaming Burnham and Tilly inside to find the clue. All of the towers have an auxiliary control panel hidden somewhere nearby and if they can find the one near the High Summit, it should be easy enough to reset any components that have failed over time. Tilly asks if there were any settlements around the other towers and Adira confirms that they all had settlements around them, but all of those settlements were destroyed when the towers fell. "So, if we don't fix this one, everyone here will die," Tilly grimly concludes. Burnham thanks Adira and Rayner and notes that one mission has just become two: find the clue and fix the tower so that the Halem'nites survive.
In sickbay, Culber and Stamets have finished checking for biological, chemical, and genetic anomalies and it turns out that Culber has a perfectly typical, healthy, and rather handsome, Human brain, meaning that there are no lasting effects of zhian'tara whatsoever. Culber is visibly disappointed, admitting to his husband that he was hoping these scans would give him an answer, a physiological cause for what Culber is feeling and then he could understand and talk about it. Culber explains that ever since , he's felt more connected and attuned to something greater than himself and greater than all of us. If there's no scientific reason for it, then it's a spiritual thing. Stamets' response is that what matters most is that his husband is okay as the scans would've picked up anything with health implications. Stamets suggests that Culber just enjoy it and the Human brain is one of the most complex things in the known universe. Culber agrees, but doesn't appear to be fully convinced.
Burnham notices that the recovered Anorah isn't happy, and Anorah explains that the last time there was a Journey, which was long ago, she ran and so did her friend Vohrahli. Vohrahli was fast and she won the race, and Anorah has been thinking about what she and Vohrahli would like as wrinkled old elders together. Anorah attempts to dissuade Burnham from undertaking the Journey as she doesn't need to reach the summit to see the gods, but Burnham has no other choice, claiming that she's dreamed of it her whole life. Anorah understands and promises to pray for her friend, leaving Burnham slightly disturbed by the conversation.
The compeers consume something that a Halem'nite passes around as Ohvahz tells the legend of Halem'no's past and the Great Mother Compeer. In ancient times, the planet was fertile and gentle, but even in such a land of plenty, the Halem'nites warred against each other and lost the favor of the gods who punished them by bringing the dust storms, in reality their ancient wars most likely destroying the ecosystem. The Halem'nites would've ended their days in thirst and dust if the Great Mother Compeer hadn't shown the gods their true selves by venturing out into the storms and traveling far to find water for her children, bringing it back while not drinking a single drop for herself even as her lungs filled with dust and her thirst was terrible, saving her children at the cost of her own life. The gods were so moved by the Great Mother's sacrifice that they brought back the rains to Halem'no. The compeers are purposefully dehydrated so that as they travel around the High Summit bearing a terrible thirst, they too will endure this test and remind the gods of the Mother Compeer and her devotion and their own devotion and earn their merciful rain. Two of the compeers are unable to stand it and drink from bowls of water that were set out, disqualifying themselves. Ravah tells Burnham and Tilly to try not to fall behind while Burnham is resigned to running the race as they need to find the clue.
As the compeers make the Journey, the Halem'nites slowly start to drop out of the race with Burnham and Tilly struggling to even keep up. Burnham notices that most of the moss on the trees that they are passing is blue, but some of it is yellow which is a genetic mutation. An eight-hundred-year-old control panel would likely be leaking radiation, which could cause such mutations. If Burnham's right, then the moss would lead them to the control panel, but if she's wrong then one of them still needs to win the race and get the clue. Calling herself the queen of endurance, Tilly chooses to continue the race while Burnham disqualifies herself by drinking from a nearby bowl of water and chases the moss. A dehydrated Tilly nearly collapses, but Ravah grabs her, stating that they want some real competition now that there's only two of them left.
The moss trail leads Burnham to where her retinal tricorder detects the control panel hidden in a rock covered in the yellow moss. Burnham sends a scan of it to Adira, who determines that the technology requires periodic maintenance, meaning that it was bound to fail eventually without it. Burnham asks how to fix it and Adira, after getting an encouraging nod from Rayner, tells Burnham that she will need to rebuild the motherboard without shutting it down by accident. Adira begins walking Burnham through the process of fixing the control panel while Ohvahz and the other compeers stop Tilly and Ravah to tempt them to drink as per the Mother Compeer's journey, and they must now complete the journey while carrying temptation. Ravah falls and spills her water, which is a disqualification as the racers can't complete the Journey with an empty bowl, making Tilly the winner. However, Tilly pours some of her own water into Ravah's bowl, allowing them to finish the race together.
Burnham's efforts to rebuild the motherboard hits a snag and a nervous Adira suggests to Rayner that they should get someone with more experience to help support the captain. Rayner reminds Adira that they were the one who had wanted to be on the bridge and Rayner wouldn't have agreed if he thought that Adria couldn't handle it. Adira has been second guessing themself ever since the time bug came on board, but that's not on them. Having successfully completed the step that she was on, Burnham calls for the last step and Adira, now with more confidence, instructs her to bypass the auxiliary power circuit by yanking it out. The malfunctioning control panel reboots, restoring full functionality to the High Summit. With the interference gone, Burnham and Tilly can now be beamed directly into the tower by Discovery, but Tilly reports that she is in the temple as she and Ravah tied. However, Tilly doesn't see the clue anywhere. Burnham reassures her friend that having gotten the control panel back online, they'll be able to transport a team over in just a few minutes.
Ohvahz finishes preparing a ritual and Ravah promises their father they will see the gods and bring the rain. Ohvahz states that the Halem'nites are so grateful to both Ravah and Tilly as their sacrifice will bless Halem'no for many seasons to come. As Ravah gives over her braclet, no longer needing it to remember their mother, the alarmed Burnham and Tilly realize that the Halem'nites intend to sacrifice Tilly and Ravah to the gods. Ohvahz locks them in the room and Discovery can't get a lock to beam Tilly out. The room, which is located high up in the tower, seals itself off.
=== Act Three ===
Gallo reports that something is scrambling their signal, and they can't get a lock on Tilly. Tilly reveals that the walls are solid tritanium, which is too dense for a transporter lock. Examining a scan of the High Summit, Rayner determines that Tilly and Ravah are in the vacuum chamber where chemicals come up the central column and mix with air and whatnot from the room above and get shot into the atmosphere to make it rain. Seeing as it's a vacuum chamber, Rayner guesses that, in the process, all of the air gets sucked out of the room, which Adira notes explains why the room is made out of tritanium: it would crumple otherwise. Ravah overhears Tilly talking so Tilly lies that she's just praying to the gods. The celling seals off as well and Ravah reassures Tilly that the gods are coming, and the gods will take their breath and replace it with their own as the air begins to run out. Tilly is sad because Ravah wouldn't be here if it wasn't for her, but Ravah is grateful as she's going to see the gods.
Ravah leads her friend to the Serenity Wall to pray together and Burnham orders Discovery to beam her in as close to the chamber as possible if they can't beam Tilly out. Rayner finds a control room right next to it, but Gallo picks up Ohvahz's life sign in it. Burnham orders Discovery to beam her in regardless of the fact that she would be breaking the Prime Directive by revealing herself to a pre-warp civilization. Although they will have to answer for the Prime Directive violation, Burnham isn't willing to let Tilly and Ravah die for no reason. Moreover, if the Halem'nites can't maintain this technology, they're going to get wiped out sooner or later. Either way, they have to do this and Rayner finally agrees, ordering Burnham to stand by.
Tilly takes interest in some symbols on the Serenity Wall which Ravah identifies as numbers to help the Halem'nites recall the five serenity prayers. If they say them, it's foretold that they'll find peace before they pass, but Tilly doesn't see any numbers. Ravah is confused as Tilly is a teacher and the numbers are in ancient Halem'nese. Ravah shows Tilly that each symbol actually stands for a number from one to five to represent each of the summits that once were with the High Summit being number three. Tilly recognizes the symbol for summit number five and Ravah explains that the gods had destroyed all of the summits but theirs, which is why the Halem'nites must sacrifice, to show the gods that they are worthy of their gift. Ravah breaks down crying, terrified of dying and admitting that they had only taken the Journey to make their father proud. Holding Ravah in comfort, Tilly suggests that the gods might figure out a way to spare them.
In the control room, Ohvahz breaks down, apologizing to his wife for failing to stop their child from taking the Journey and not being selfish when all of their people are suffering for each other. Much to Ohvaz's shock, Burnham beams in and asks him to open the door. Ohvahz denies Burnham as just being a vision brought on by his grief and selfishness. Burnham finally breaks through to him by revealing that the High Summit is actually just a piece of technology placed here hundreds of years ago by an alien race and the sacrifices don't bring the rain but rather technology. However, Ohvahz quickly slips back into denial and Burnham desperately tries to figure out how to open the door as Tilly and Ravah running out of air, leaving Tilly barely conscious. Burnham asks Tilly to talk to Ravah, hoping that they can help her to reach Ohvahz.
Tilly asks Ravah about their mother and Ravah tells Tilly about how their mother used to sing Ravah a song to help them sleep when they were still together. Tilly asks Ravah to teach it to her so Tilly can sing it to them while Ravah falls asleep. Ravah begins humming the tune which Burnham can hear over her subcutaneous comm and she starts humming it to Ohvahz, explaining that she can hear it from the other room thanks to her technology. Ravah remembers their mother singing that song so many years ago and they are dying now, and they don't want to die. Ohvahz asks if Burnham is a god, but Burnham explains that she is just a person from really far away, almost as far away as the people who put the technology here. Burnham wants to help Ohvahz save his child and her friend from dying a needless death. Ohvahz is conflicted, but Burnham suggests that her presence here may be the result of divine intervention and the rains will come whether or not Ravah dies, and she begs the man to trust her and let Tilly and Ravah live. Finally convinced, Ohvahz turns a handle hidden by a carpet, reopening the vacuum chamber, but Ravah isn't breathing. With the chamber reopened and no longer blocking the transporters, Culber quickly beams in with a medical team and revives Ravah.
=== Act Four ===
As Culber works on Rahva, Ohvahz looks in wonder at a holographic projection of Halem'no as seen from Discovery. Receiving an encouraging nod from Culber about Ravah's condition, Ohvahz asks about the alien race that give the Halem'nites the High Summit to save them from the dust storms. Burnham explains that the Denobulans value one another greatly as the Halem'nites do, they come from a world much like Halem'no with massive storms and they built weather towers to keep the storms on their homeworld at bay. Burnham guesses that in their travels, the Denobulans felt a connection to the Halem'nites and wanted to help them.
Burnham warns Ohvahz that the High Summit is failing and while it's fixed for time being, the tower will eventually stop working if it's not maintained, but the Federation can show the Halem'nites how. Ohvahz thanks her and asks if this means that there's no gods and what there is if the gods don't exist, but Burnham tells him that there's still what you believe and nothing that Discovery has shown him means that gods don't exist or that the Journey of the Mother Compeer didn't happen. The only difference is that now the Halem'nites know that there are also other races out there. Ohvahz is unsure of what to say to his people since the sacrifices unite the Halem'nites and help them to see their common purpose. Ohvahz fears how his people will react if this is taken away so suddenly. Past attempts to stop the sacrifices have been met with violence and upheaval which Burnham acknowledges is wise to consider. However, there are those amongst the Halem'nites who seem ready to move beyond the sacrifices such as Anorah who finds order in the Halem'nites' commitment to one another. Anorah told Burnham that the sacrifices aren't necessary to bring one closer to the gods and maybe there are others ready to understand that too. "Beliefs can evolve. Denying that can cause almost as much chaos as the worst storm." Culber interrupts with the news that Ravah will wake soon, suggesting that under the circumstances, they should see their father when they do.
Ohvahz tends to his child, putting his wife's bracelet back on Ravah's wrist, while Tilly wonders if they did a good thing. Burnham jokes that it's a good thing that Tilly is still alive due to the amount of paperwork that she'd have to fill out for losing a perfectly good Starfleet officer in addition to all of the paperwork that Burnham is going to have to fill out for breaking the Prime Directive. Tilly leads Burnham to the Serenity Wall and draws her attention to the symbol that Tilly had earlier taken an interest in. The symbol matches the scratches on the side of the vial containing the pure distilled water from Halem'no. Tilly explains that they're numbers in ancient Halem'nese standing for each of the five weather towers and they are in the third tower. The mark on the vial was telling them that the clue is in tower five on Halem'no.
Ravah awakens and asks if their father is with the gods as well, becoming concerned that the rains won't come after learning that they are still alive. Ohvahz suggests that devotion might mean being able to hear when the gods tell us something new. He is very proud of Ravah who is full of light, courage, and song, just like their mother. The two embrace and as they move to leave, it starts raining again for the first time in a long time coming in through the holes in the celling.
On Discovery, Culber finds Booker using the controls of a shuttle as a flight simulator, preferring it over a holodeck simulator which he can always tell is fake. Culber bring Booker his grandmother's mofongo, replicator fresh. As they eat, Culber recalls how Booker had earlier asked him if he gets tired of having all of the answers. Although it was just a joke, Culber admits that he doesn't grow tired of having all of the answers. Culber is having a spiritual awakening or maybe just seeing a truth that he's always known, but nothing else explains it ever since zhian'tara. Booker thinks that it sounds wonderful, but Culber doesn't think that Stamets really understood when Culber had told his husband about it or that Stamets ever will. Booker suggests that it doesn't matter and that the Human tendency to consider something less meaningful if it's just for themselves is an odd quirk. Booker remembers Burnham dealing with it despite the fact that being alone was the oldest and closest friend she ever had. However, it just made Booker love her and Culber realizes that Booker misses her, specifically what they had together. Culber asks if he thinks that he can get it back, but Booker dodges the question.
Burnham and Tilly add the map piece that they recovered from tower five to the rest of the map. The next clue was a metal card attached to it with some kind of Betazoid text inscription on it which Stamets is analyzing to see where they have to go next. Tilly wonders what Dr. Kreel was trying to tell them by hiding the clue on Halem'no. Burnham muses that Kreel couldn't have known that leaving behind a weather tower would lead the Halem'nites to sacrificing one another. Tilly notes that technology is a massive responsibility and Burnham guesses that that might be the real message: when they find the Progenitors' technology, they need to be incredibly careful with it. Lieutenant calls in with a message from Federation Headquarters that the Locherer just found Moll and L'ak and Admiral Vance wants them to jump to the Locherers location immediately. Excited, Burnham orders Christopher to lock in the coordinates.
Discovery moves out of Halem'no orbit and spore jumps away.
== Memorable quotes ==
"I know it's eccentric of me, but I–I do love the feel of paper. And this isn't replicated either. This is a genuine 21st century legal pad."
"Where did you even find that?"
"Like I said, I'm resourceful."
:- Kovich, providing Burnham with the names of the scientists who hid the Progenitor's technology
"They requested more time up here. I thought they were ready."
"Didn't necessarily mean today."
"No time like the present."
:- Rayner and Adira, while on Discoverys bridge
"Wow, you can take the "xeno" out of the anthropologist but you can't take the anthropologist out… huh. No, I lost it. Uh… we could really use you at the Starfleet Academy."
:- Tilly, as Burnham goes into detail of the "whistlespeak" of the Halem'nites
"The Human brain, with its billions of neurons, each with thousands of connection points, is one of the most complex things in the known universe. So… enjoy it."
"Right."
:- Stamets, when Culber tells him he has been having a spiritual awakening since experiencing zhian'tara
"They've all got to get water at some point, right? And we have endurance. We have… Starfleet training!"
"Yeah, keep telling yourself that."
:- Burnham and Tilly, dehydrated and exhausted during the race
"Go chase your moss. I'm the queen of endurance!"
:- Tilly, to Burnham
"No, don't give up now, compeer. It's just the two of us left and I want some real competition."
"You're a little shit, you know that?"
:- Ravah and Tilly
== Background information ==
=== Title ===
* By , this episode's title had been revealed by the Writers Guild of America West. 
* The title was officially confirmed on . 
=== Cast and characters ===
* Doug Jones (Saru) does not appear in this episode and is not credited in the opening credits.
=== Story and script ===
=== Production ===
=== Reception ===
== Links and references ==
=== Starring ===
* Sonequa Martin-Green as Michael Burnham
* Anthony Rapp as Paul Stamets
* Mary Wiseman as Sylvia Tilly
* Wilson Cruz as Hugh Culber
* Blu del Barrio as Adira Tal
* Callum Keith Rennie as Rayner
;and
* David Ajala as Cleveland Booker
=== Guest starring ===
* David Cronenberg as Kovich
* Annabelle Wallis as Zora 
* Alfredo Narciso as Ohvahz
* June Laporte as Ravah
* Marium Carvell as Anorah
* Maria del Mar as Culber's grandmother 
=== Co-starring ===
* Orville Cummings as Lt. 
* Natalie Liconti as Lt. Gallo
* Christina Dixon as Lt. Cmdr. 
* Molly Lewis as Whistlespeaker
===Uncredited co-stars=== 
* Pamela Mars as Discovery bridge crewmember
* Shelley Owens as Discovery medical crewmember
=== References ===
Betazoid; ; ; compeer; Denobula; Denobulan; ; Dry Lands; DSC-04; ; Halem'nese; Halem'nites; Halem'no; Healing Grove; High Summit; Infinity Room; isolinear chip; Journey of the Mother Compeer; ; L'ak; legal pad; ; Millennium Celebration; mofongo con pollo al ajillo; Moll; Mother Compeer; ; Prime Directive; Progenitors; retinal tricorder; Romulan; ; ruled paper; Spanish language; Starfleet Academy; subcutaneous transponder; T'Prasi; Terran; time bug; (planet); Trill (species); universal translator; Vellek; ; weather modification tower; whistlespeak; Zhian'tara
=== External link ===
* 
Category:DIS episodes
de:Die Pfeifsprache
es:Whistlespeak
fr:Whistlespeak (épisode)