Conspiracy ( episode ) After Captain Picard receives a dark warning from an old friend , the " Enterprise " - D returns to Earth to stop an alien invasion from taking over Starfleet Command . Summary . Teaser . While en route to Pacifica for a mission , Jean - Luc Picard receives a code 47 emergency message from Walker Keel , an old friend who is captain of the . Keel asks Picard for a secret rendezvous on the abandoned mining colony on Dytallix B . Even though it is a secured channel , Keel insists they meet face to face . Act One . Picard quickly arrives on the bridge and asks Data if he knows Dytallix B . He orders the helm to travel there immediately , with no record of the change and no communication to Pacifica . He goes to his ready room , leaving William T . Riker to wonder what is going on . On arriving at Dytallix B , Picard meets alone with Walker and two other captains , Tryla Scott and , who , after confirming Picard ' s identity with a series of questions about his past , tell him about their suspicions of a conspiracy of some sort reaching up to the highest levels of Starfleet Command . They don ' t have all the answers , but they cite recent suspicious orders and deaths . They are convinced that people , even top - level personnel , are " changing " somehow . Keel already suspects his first officer and chief medical officer . The sign of the change appears to be memory loss of long - term memories . They ask that Picard stay vigilant . Act Two . After returning to the " Enterprise " - D , he first consults Deanna Troi , saying he believes Keel and trusts him as a friend , even though he is violating Starfleet regulations . Picard looks into the matter , having Data review Starfleet directives of the past six month s . While Data is reviewing the records , the continues on to Pacifica , but along the way encounters an unusual disturbance in a nearby sector . Picard re - directs the " Enterprise " toward it , and they eventually identify it as shipwreck debris . Speculating that it could be one of the three ships they encountered at Dytallix B , Worf informs them that based on the volume of debris , it could only be the , Walker Keel ' s ship . Act Three . In light of Keel ' s death , Picard tells Riker about the suspicions Keel voiced in the observation lounge and connecting them with Rear Admiral Quinn ' s earlier that year . During their conversation , Data enters and reports what he has found : during the past six months there has been a great deal of " " uncustomary reshuffling of personnel – usually in the command areas " " of a select number of starbase s . Furthermore , the new officer s have had a great deal of contact with the highest levels of command . Data hypothesizes that the reorganizations are an attempt by a hostile force or individual to control important sectors of Federation territory . Faced with this information , the " Enterprise " - D returns to Earth . Upon entering orbit , the " Enterprise " - D is contacted by three admiral s from Starfleet Command , requesting an explanation for their return . Picard states that he would prefer a discussion of that sort occur in private ; the three admirals convene for a moment , then invite Picard and Riker to dinner at Starfleet Headquarters for the discussion to take place . Quinn says that he will not be able to attend the dinner , but that he would like to see the " Enterprise " - D again . Just before he beams up , he looks at a scorpion - like creature he has in a case . Act Four . When Quinn is on board the " Enterprise " - D , he bluffs his way through references to old times , stating that his earlier perception of a threat to the Federation was merely a metaphor for the " tumultuous process " of assimilating new species into the Federation . Picard realizes that Admiral Quinn is an impostor of some sort and tells Riker to observe Quinn closely while he beams down alone to dinner . Also , he wants Doctor Crusher to give him a medical examination under false pretenses ; after Riker reaches his conclusions , he is to join Picard on Earth , in force if necessary . Picard then beam s down and meets with Rear Admiral Savar and Vice Admiral Aaron , as well as Dexter Remmick . On the ship in the guest quarters , Quinn offers to show Riker the creature and tells him about it . It was discovered by a Starfleet survey team on an uncharted planet , and Quinn refers to it as " a superior form of life " . When Riker says he ' ll get his science officer to examine it , Quinn grabs his arm very strongly , saying the creature will only like Riker . After a brief scuffle , in which Quinn displays amazing strength , Riker is knocked unconscious , but not before calling security . Worf and La Forge arrive , calling a medical emergency . Quinn says that Riker slipped and hit his head , and then announces his departure . When they try to detain him , however , he throws La Forge out into the corridor , his body knocking down the door . He turns to Worf . Act Five . He similarly beats Worf before being repeatedly phaser ed with increasingly powerful stun settings into unconsciousness by Dr . Crusher . In sickbay , Crusher ' s scan s show that Quinn really is Quinn , but she discovers a bizarre appendage sticking out of the back of his neck . On Earth , the two admirals try to subtly persuade Picard that there is in fact no conspiracy . However , they reveal they know his first officer by name , which is unusual . Furthermore , they know the " Horatio " is destroyed , and they blame Keel ' s negligence . Dinner is announced , so Picard takes a moment to contact Riker . Crusher answers on Riker ' s combadge , as Riker is unconscious . Crusher informs Picard that a parasitic creature of some sort has taken control of Quinn and all his brain functions . The spike at the back of Quinn ' s neck appears to be a gill , which is a helpful indicator of those who have been taken over by one of the creatures . Crusher states her doubts about removing the creature , believing it would kill Quinn . She instructs Picard to set his phaser to kill rather than stun , which has little effect on the creature or its host ; Picard , however , believing that no one beams down to Starfleet Headquarters armed , has no phaser with him at all . Picard goes in to dinner . The dish being served is a bowl filled with worm s . Picard is disgusted , and realizes that everyone at the dinner has been infiltrated by the alien s . He gets up to leave , and runs into Riker . Riker has also apparently been taken over by the creature : he has a gill in his neck . So , too , has Captain Scott . The " conspirators " announce that they have known of Picard ' s intentions the whole time . They talk of their plan to infiltrate the " Enterprise " - D . Riker moves to eat , but instead he pulls out a type 1 phaser and shoots the dining security guard . When Captain Scott draws her phaser at Riker , Picard grabs at her arm and throws off her aim , allowing Riker to shoot her as well . However , Admiral Savar begins to subdue Riker with a Vulcan neck pinch . Picard then grabs the Captain Scott ' s phaser and uses it to take down Savar . Admiral Aaron flees the dining room , and Picard and Riker pursue and shoot him in the hallway after he returns fire . The admiral falls to the ground , and the parasite infesting him crawls out of his mouth and goes under a nearby door . They follow it to find Remmick sitting in a chair . He turns to look at it , unconcerned ; Riker goes to shoot it , but Picard stops him , as the creature crawls up Remmick and enters his mouth . He swallows it , and it begins moving around in his neck . " " We mean you no harm " " , he says as he stands , his neck noisily bulging in and out . " " We seek peaceful coexistence " " . Picard and Riker open fire with their phasers , knocking Remmick back into the chair . Riker aims higher and destroys Remmick ' s head , the outer layer of skin vaporizing and the rest exploding . Remmick ' s chest cavity begins to dissolve and a large creature breaks through with several blood soaked parasites trickling behind , screaming at the two Starfleet officers . With a disgusted look on his face , Picard opens fire again with Riker following suit , both phasers continuing until the creature is vaporized , leaving several blood soaked parasites around the chair and floor , and the decapitated smoldering remains of what was once Lieutenant Commander Remmick . Back aboard the " Enterprise " - D , Picard notes in his log that Admiral Quinn will make a full recovery , and with the death of the " mother creature " inside of Remmick , the remaining parasites died while Riker reveals that Dr . Crusher had simulated the gill on the back of his neck in order to fool everyone , including Picard . As the " Enterprise " - D moves on into space , Data theorizes that Remmick had been transmitting a homing beacon before he died and that should the parasites receive it , they would know where to find Earth . Memorable quotes . " " It ' s about Starfleet . About something we ' ve always considered to be impossible . " " " " You owe me , and you owe it to yourself to hear what I have to say . Something is beginning . Don ' t trust anyone . Remember that , Jean - Luc . Don ' t take anything for granted . " " " " It won ' t like your science officer . It DOES LIKE YOU ! Vitamins . . . they do wonders for the body . " " " " Friendship must dare to risk , Counselor , or it isn ' t friendship . " " " " Apologies , Captain . We had to be sure you were really you . " " " " I ' m glad , Jean - Luc . I ' m glad you ' re still one of us . Tell Beverly I . . . I said " hello " . " " " " Captain , you must set your phaser on kill . Stun has little effect . " " " " Doctor , one does not beam down to Starfleet Headquarters armed . " " " " If I could see , I ' d be seeing stars . " " " " You don ' t really think we were in the dark about your intentions , do you ? " " " " Patience is one of our virtues , Captain . We didn ' t go after you ; we allowed you to come after us . " " " " More dramatic that way , don ' t you think ? " " " " Yes . The one thing both races share is a love of theater , and you ' ve put on a fine show . " " " " You don ' t understand . We mean you no harm . We seek peaceful co - existence ! " " Links and references . References . 2364 ; admiral ; adrenal gland ; Altairian Conference ; ; Andonian tea ; aquarium ; Arcadian ; bed ; biobed ; Bolian ; bracelet ; brain ; bridge ; captain ; cargo ; carpet ; cloud ; code 47 ; comnet database ; conspiracy ; conspiracy theory ; ; corridor ; ; debris ; Delaplane ; desk ; desktop monitor ; Dytallix B ; Dytallix Mining Company ; Earth ; Fleet Operations Center ; frigate ; Galaxy class decks ; Golden Gate Bridge ; governor ; guest quarters ; heavy cruiser ; holodeck ; homing beacon ; ; " Horatio " first officer ; " Horatio " medical officer ; hypospray ; ; ; Keel ' s brother ; ; Klingon ; Klingonese ; Luna ; McKinney ; medical tricorder ; Milky Way Galaxy ; Mira Antlia ; Mira Antlia system ; Mira Antlia V ; model ; NCC - 7100 ; neck ; parasitic being ; parasitic beings planet ; neutron star ; number one ; observation lounge ; orbital shuttle ; orbital shuttle 5 ; Outer Rim ; Pacifica ; PADD ; painting ; rag doll ; ramp ; ready room ; rear admiral ; Relva VII ; ; replicator ; sabotage ; San Francisco ; sculpture ; Sector 63 ; security code ; senility ; sickbay ; ; skant ; Sol ; Sol sector ; SS 433 ; Starbase 12 ; star chart ; Starfleet Command ; Starfleet Headquarters ; star system ; survey ; swimming ; Tau Ceti III ; Tellarite ; ; transporter room ; turbolift ; type 1 phaser ; type 2 phaser ; Type 7 shuttlecraft ; United Federation of Planets ; Unnamed Federation space stations ; unnamed medical tools ; unnamed orbital shuttle ; unnamed plants ; utility uniform ; viewscreen ; VISOR ; vitamin ; voice print identification ; Vulcan ; Vulcan nerve pinch ; Vulcan salute ; window ; worm