Twilight ( episode ) The effect of a Delphic Expanse anomaly leaves Archer unable to form any new long - term memories . Twelve years later , he wakes up one morning and is stunned to learn the outcome of the Human - Xindi conflict , including the loss of Earth , and the near - annihilation of the Human race . Summary . Teaser . Jonathan Archer wakes in his quarters in the midst of battle . He rushes to the bridge , demanding to know what ' s happening . T ' Pol , dressed in a command division Starfleet uniform , orders security to take him back to his quarters . Hoshi interrupts both of them , and everyone stares at the viewscreen as the Xindi weapon emerges from a subspace vortex and fires on Earth . The weapon ' s powerful energy beam boils the oceans , and the surface begins to splinter . As the bridge crew look on in horror , the molten Earth breaks apart and finally explodes . Act One . Archer wakes in a small house and is puzzled to find himself with visible grey hair , cut in a Vulcan - like style . Emerging into the house he finds T ' Pol , who now has far longer hair and addresses him by his first name . Archer is puzzled , as T ' Pol insists that he sit down for breakfast , promising the full story . She asks him what the last thing he remembers is , and he replies that they were leaving the command center . T ' Pol reveals it has been twelve years since then . . . Twelve years earlier , Archer and T ' Pol are discussing the upcoming showing of " Rosemary ' s Baby " on movie night . Suddenly the ship rocks as it is hit by anomalies . A powerful one hits and runs through the corridor where Archer and T ' Pol are . They try to escape but are caught by the wave , and although they escape serious inury T ' Pol is trapped by debris . As another wave is about to hit , Archer tries to free T ' Pol despite her urging him to leave . Although he is successful and she escapes , Archer is struck by the full force of the anomaly and is left unconscious . Archer wakes up in sickbay under Phlox ' s care . Although Archer believes only an hour or so has passed , Phlox reveals he ' s been there for three days . He explains that the anomaly has infected Archer ' s hippocampus with interspatial parasite s that have left him with , preventing him from forming any long - term memories since the incident . Phlox promises to do everything he can to find a cure . As a result of his profound disability , Archer was relieved of his command and replaced by T ' Pol , who accepted a field commission as a captain in Starfleet . After the change in command , " Enterprise " was unable to find the Xindi weapon . When " Enterprise " drew close to the weapon in 2154 , it came under attack by Xindi - Reptilian s . Many crewmembers , including Travis Mayweather , died in the assault . The ship also suffered severe damage limiting it to warp 1 . 7 , mainly due to a ramming maneuver T ' Pol used to defeat the Reptilians . By the time " Enterprise " reached the Azati Prime system , the weapon had already been launched . After destroying Earth , the Xindi continued searching the galaxy , determined to hunt down and kill all Human s . Almost all of Humanity was ruthlessly wiped out . Archer goes out of the house crying after he hears the bad news . Act Two . T ' Pol explains to Archer that " Enterprise " , " Intrepid " , and another two Starfleet starship s led a convoy of around 6 , 000 surviving Humans to Ceti Alpha V . On this remote world , a secret , desolate refugee camp was built to house the remnants of Human society . " Enterprise " , under the command of Charles Tucker , was stationed in orbit with the remaining Starfleet vessels . Archer retired to the civilian community on the surface . T ' Pol , refusing an offer to return to service with the Vulcan s , resigned her Starfleet commission and chose to remain at the refugee camp to care for Archer , having felt an intense obligation to care for him since he saved her from the anomaly , an action which resulted in his disability . For over nine years , this last outpost of Humanity had survived by remaining hidden from the Xindi . Concluding her story , T ' Pol says , " At this point you often wonder if you are the victim of some elaborate deception . " Archer admits that the thought did cross his mind . T ' Pol makes certain Archer believes her by reminding him about Margaret Mullin , a woman he once asked to marry him . Archer asks how T ' Pol could know so intimate a detail , and she explains that their relationship has " evolved . " Shortly after T ' Pol explains all this , Phlox arrives from Denobula , also looking a little older . He is ready to try out a revolutionary new treatment for Archer ' s condition , which he has been developing for nearly a decade . Many of Phlox ' s colleagues in the medical community were convinced that nothing short of a subspace implosion would destroy the parasites ( a treatment which , of course , would also kill the patient ) . Phlox persevered and developed an alternative but energy - intensive treatment which can target and destroy the parasites without any harm to Archer . With T ' Pol , they return to " Enterprise " , where the warp core will provide the energy necessary for the treatment . Act Three . Archer receives a hero ' s welcome aboard his old ship . After the first phase of treatment , Phlox and T ' Pol examine records of Archer ' s brain scans from twelve years ago and realize that the parasites they have eliminated in the present have apparently disappeared from the past as well . If Phlox were to successfully complete the treatment and eliminate all the parasites , then it would be as if the parasites had never existed . This would effectively change history , and Archer would never have suffered from memory loss . Perhaps with Archer in command , " Enterprise " would have stopped the Xindi weapon , Earth would not have been destroyed , and Humanity would not have been nearly wiped out . Unfortunately , Archer ' s treatment is cut short when " Enterprise " detects Yerdrin Lek , a Yridian spy , near Ceti Alpha . Lek tips Tucker off to the fact that the Xindi have found the last outpost and are on their way to finally annihilate the last of the surviving Humans . With " Enterprise " s power needed for battle , T ' Pol and Phlox cannot complete Archer ' s treatment . Hoshi reports to Captain Tucker that six Xindi ships are entering the system . Act Four . The battle begins . At first " Enterprise " and the other Earth vessels manage to ambush and disable two enemy ships , but ultimately Humanity ' s last stand does not go well – the " Intrepid " loses its port nacelle and is forced to withdraw , and " Enterprise " ' s bridge is destroyed , literally torn from the rest of the ship , presumably killing the bridge officers . As Xindi - Reptilian soldiers board the now - adrift starship and start gunning down the crew , Archer recalls that Phlox said a subspace implosion would destroy the parasites . Desperate and with nothing to lose , Archer , T ' Pol , and Phlox feverishly work at the warp core to trigger an implosion . With Xindi soldiers firing around them , Phlox and T ' Pol are killed . Archer is also shot , but with his last breath , he manages to push the final lever which initiates the subspace implosion , destroying the parasites in his brain ( and " Enterprise " with them ) . In 2153 of the new timeline , Archer wakes up in sickbay after saving T ' Pol from the spatial anomaly . Although Archer suffered a concussion , Phlox expects a full recovery . Memorable quotes . " " You ' ll enjoy it . " Rosemary ' s Baby " . It ' ll scare the hell out of you . " " " " In the corridor , when the anomaly hit , I urged you to leave me behind – if you had , it ' s likely " I " d be the one suffering from this . . . condition . " " " " Fortunately , I don ' t take orders from you . " " " Captain . . . " I never expressed my gratitude for what you did . " " " " I suppose there ' s not much point in thanking me . . . a few hours from now , I won ' t remember . " " " " We ' ve taken nine prisoners , but the brig was only designed for two . I ' m not sure what to do with the others . " " " " Blow ' em out the airlock ! " " " " Put them in crew quarters under heavy guard . " " " " For now , the best I can give you is warp 1 . 7 ! " " " " We ' re not going to get very far at that speed . " " " " This planet is barely Minshara - class . Maybe we should ' ve picked one with a little more blue and green on it . " " " " Our relationship has " evolved " over the years . " " " " Exactly how " far " has it evolved ? " " " " Did everyone get their own ship while I was gone ? " " " " It couldn ' t have been easy for you , telling me the same story over and over again for twelve years . " " " " I don ' t always tell it in detail . " " " " I hope I ' ve told you this before , but . . . I ' m very grateful for everything you ' ve done for me . " " " " Your engineers won ' t let us continue the captain ' s treatment ! " " " " Those were my orders – look , I ' d do " anything " to help the captain , but we ' ve got bigger problems at the moment . " " " " This may be the " only " solution to your problems , captain . " " " " Destroying these parasites is most likely the key to saving Humanity – and " Earth . " " " This image was taken a few minutes ago . You can see the region where I eradicated the first cluster of parasites ? It ' s gone in this image as well . . . This scan was taken over twelve years ago . The cluster has disappeared from " all " the scans I ' ve taken over the last twelve years – it ' s as though it never existed at all . " " " " By destroying the organisms in the present , we appeared to have neutralized them in the past . " " " " We know they ' re from another spatial domain . Apparently they also exist outside of time – if we can eliminate all of the parasites , it ' s possible the captain ' s infection will " never have occurred ! " " " If the Xindi are on the way , there ' s very little we can do to stop them . " " " " Well we can ' t just run up the white flag . " " " " Our shields are holding . Nice to know they work in combat . " " " " Remind me to send a thank you note to General Shran . " " ( Horrified ) " " The bridge is gone . . . " " ( Realizing there ' s no one to stop her from treating Archer ) " " T ' Pol to Phlox . . . meet us in engineering . We ' re going to finish the procedure . " " " " We don ' t have time to worry about parasites right now . " " " " That ' s not necessarily true . " " " " I ' m sorry , Captain – the chamber ' s been damaged . " " ( Archer initially looks up in horror , before remembering that there " was " another way ) " " Didn ' t you say we could destroy the parasites with a subspace implosion ? " " " Yes , " but that would . . . " " " " Can we create one ? " " " " We would have to overload three plasma injectors – that would send a feedback pulse through the reactor . " " " " You ' ll destroy the ship ! " " " " At this point , it won ' t make much of a difference ! " " " " You two , get to a shuttlepod . They ' re only after Humans – if this doesn ' t work out , you ' ll still have a chance . . . " ( the Vulcan and Denobulan exchange a quick glance , and T ' Pol walks up to the warp core to render assistance ) " . . . That ' s an order ! " " " " With all due respect , you were relieved of command . " " " " You could ' ve been seriously injured – I told you to leave me behind . " " " " Fortunately , I don ' t take orders from you . " " " " You know . . . you ' d make a wonderful nurse . " " Links and references . References . Air Group Ten ; Alpha Centauri ; alternate timeline ; anterograde amnesia ; antimatter inducer ; antiproton beam ; boatswain ' s whistle ; Ceti Alpha system ; Ceti Alpha V ; chromosphere ; classroom ; Command Council ; concussion ; Delphic Expanse ; Denobula ; Denobulan shuttle ; distress call ; duranium ; Earth ; feedback pulse ; field commission ; flight school ; ; garbage scow ; general ; hippocampus ; information dealer ; interspatial flux ; interspatial parasite ; " Intrepid " ; ; Jupiter Station ; Martian colonies ( Mars ) ; millicochrane ; Minshara class ; microcellular scan ; ; Mutara sector ; Mutara system ; neurosurgeon ; phase cannon ; plasma injector ; plasma torch ; Porthos ; quantum theorist ; radiolytic signature ; ; reserve power ; " Rosemary ' s Baby " ; Rigelian flame gem ; sentry probe ; shields ; ; subspace buoy ; subspace implosion ; transporter ; turbolift ; Vega colony ; Vulcan ; ; Vulcan database ; Vulcan High Command ; warp coil ; white flag ; Westgate Avenue ; Xindi - Insectoid starship ; Xindi - Reptilian warship ; Yridian s ; ; Zefram Cochrane ' s statue Unreferenced material . Jack Archer