Assignment : Earth ( episode ) The " Enterprise " travels back in time to 1968 , where the crew encounters the mysterious Gary Seven who claims to be sent by advanced beings trying to help Earth . " ( Season finale ) " Summary . Teaser . After Captain Kirk finishes his log entry , suddenly the " Enterprise " is rocked , and Spock reports that they appear to have intercepted someone ' s transporter beam . Kirk remarks that there were no such devices in the 20th century . Spock maintains that someone is beaming aboard . Spock discovers that the transporter beam originates more than a thousand light year s away . Scott finds that difficult to believe , stating that no transporter beam could reach that far , not even in their time . Suddenly a man in a dark suit , holding a black cat , appears on the transporter pad . Act One . The strange man asks Kirk why he was intercepted and who his interceptors are . Kirk identifies himself and tells the man that he is aboard the United Space Ship " Enterprise " . The man asks what planet they are from , and Kirk says they are from Earth . This the man refuses to believe , because 20th century technology would not allow for a ship like the " Enterprise " . But when he notices that Spock is a Vulcan , he realizes the ship is indeed from the future and asks to be beamed down to Earth . As security arrives , the man identifies himself as Gary Seven , calling himself a man from the 20th century , and gives his cat ' s name as Isis . Kirk states , however , that Human s of the 20th century do not go beaming around the universe . Seven explains that he has been on another planet , one much more advanced , and that he was beaming to Earth from that planet when the " Enterprise " intercepted him . When Kirk asks which planet it is , Seven says that the inhabitants wish their planet to be kept secret and that even in Kirk ' s time , it will remain unknown . Seven reiterates that he is of this time period and adds that , if Kirk does not allow him to do what he needs to do down on Earth , then Kirk will have changed history . But Kirk , unsure that Seven is telling the truth , decides to keep him aboard the ship until that can be determined . However , Seven tries to escape , overpowering the security guards , and he even shrugs off Spock ' s attempt at a Vulcan neck pinch . Seven is only subdued by a phaser stun from Kirk . Kirk calls Dr . McCoy and asks him to examine the mysterious man in the brig to determine if he really " is " Human . In the briefing room , Spock , who is stroking Isis , mentions that he finds himself strangely drawn to the cat . Ensign Chekov reports that analyzing the direction Seven ' s transporter beam came from show no habitable planets in that area of the galaxy and Scott says that they will not be able to analyze the transporter beam , as it had fused their recording circuits . The beam could have brought him across tremendous distances across space , and perhaps even through time ; there is , quite simply , no way to know . Spock also mentions that current crises on Earth could fill a tape bank , noting that , on this one day alone : " " There will be an important assassination today , an equally dangerous government coup in Asia , and , this could be highly critical , the launching of an orbital nuclear warhead platform by the United States , countering a similar launch by other powers . " " Kirk and Spock briefly discuss the nuclear arms race and how that once the sky was filled with orbiting H - bomb s , the slightest mistake could have brought one down , setting off a nuclear holocaust . Seven soon escapes from the brig using a device called a " servo , " disguised as a pen , to deactivate the force field and put the guard to sleep . Back in the briefing room , McCoy tells Kirk that Seven is indeed Human , but that also that his is a totally perfect body , without a physical flaw at all within him . This raises the possibility that he could be an alien taking Human form , and Spock points out again that Seven could be telling the truth . Kirk laments that neither of them is telling him anything definite . At that point , Isis jumps out of Spock ' s lap and leaves the briefing room . Security then alerts them that Seven has escaped . In the transporter room , where Isis rejoins him , Seven renders Lemli and Leslie unconscious with his servo and beams down before Kirk can stop him . Act Two . Seven materializes inside a transporter chamber , disguised as a vault concealed behind a sliding rack of glasses , in what appears to be an otherwise normal office . Seven accesses a computer behind the bookcase . Seven asks for the locations of agents 201 and 347 . The computer asks Seven to identify himself and Seven tells the computer to check his voice pattern , and it will identify him as Supervisor 194 , code name Gary Seven . The computer recognizes his voice pattern but is unaware of a Gary Seven being assigned to this planet . Seven then tells the computer that he is a Class One supervisor and that the computer is to override all previous instructions and answer his questions . The computer identifies itself as a Beta 5 computer capable of analytical decision and forces Seven to prove himself by describing the mission of the two agents that were sent here . Finally Seven , after griping that he has " little love for Beta 5 snobbery , " relents and tells the computer that missing agents 201 and 347 are a male and a female descendant , respectively , of Humans taken from the Earth approximately six thousand years ago ( circa 4000 BC ) and that they were specially engineered and trained for this mission . The problem is that on Earth , its science and technology have progressed faster than its political and social knowledge have . Their mission is to prevent Earth from destroying itself before it can become a peaceful society . The computer states that Seven ' s information , while incomplete , will suffice and tells Seven that the agents have not reported for three days . Seven tells the computer to immediately begin a search and begins describing how to do so when the computer tells him it is aware of proper search procedures . Meanwhile , back aboard the " Enterprise " , Kirk , Spock , and Scott are trying to determine where Seven had beamed down . Scott says that they can get to within approximately one thousand meter s of where he had gone . Spock reminds Kirk that following him down is very risky because they may end up accidentally doing something to alter history . Kirk says he knows but he must also know if Seven is being truthful with them . Kirk tells Scott to have ship ' s store s prepare the proper costumes and then prepare to beam them down . In his apartment , Seven learns that the agents ' mission was to disable a rocket that will launch an American orbiting nuclear platform which is a counter - move to an opposing country that has already done the same . This appalls Seven , who says that this arms race is the same kind of nonsense which almost resulted in the destruction of planet Omicron IV , which the Beta 5 computer confirms . Seven asks if the warhead has been disabled , but the computer says both that it has not been and that there are just under ninety minutes before launch . Seven says that unless the agents are immediately located , he will have to undertake their mission in their absence . Having beamed down , Kirk surreptitiously calls Scott with his communicator and tells him to lead them to Seven . Scott gives Kirk the coordinates and Kirk and Spock proceed . The computer provides Seven with various pieces of false identification , including identification listing Seven as a colonel with the CIA , a lieutenant in the NYPD , and a colonel with the NSA . It also produces a map of McKinley Rocket Base . At that moment , a young woman walks in and asks if anyone is in . Seven steps out and demands to know where she has been . Seven means where she has been for the past three days . The woman sees no reason to tell him and asks who he is . Seven asks where 347 is . But she neither knows nor understands , jokingly replying that perhaps he is with 348 . She then threatens to call the police . After insisting that she sit down , Seven , wrongly believing her to be agent 201 , tells her that he is " Supervisor 194 , code name Gary Seven " and that he needs a complete report of all that she has done in the last three days . As the woman prepares to start typing , Seven flips a switch and tells her not to bother with her hands . When she wonders how she will type , the typewriter begins typing everything she says . This gets the young woman very frustrated , and after she yells at the typewriter to stop typing what she says , Seven finally switches it off and she says that she will quit . Seven then realizes that she is not acting . Using his servo , he locks the door ; he then accesses the computer and has it identify the woman in the room . The Beta 5 identifies her as Roberta Lincoln and says that she is a secretary hired by Agents 347 and 201 . Realizing the terrible mistake he has made , Seven asks Roberta what work her employers said they were doing and she says they were doing research for a new encyclopedia . Seven tells her she can go , though she will not be helping her country , unless of course , she does not care for her country . When Roberta protests that she does , Seven tells her that thanks to his incompetence , he has made her aware of some top secret devices vital to the security of the nation . He shows her his false CIA ID and she accepts that it is legitimate . Isis opens the door and meows at Seven . Seven explains to Roberta that Isis is a trained cat and asks Roberta not to let anyone in and she agrees to do so . Out on the street , Kirk calls Scott again , and Scott tells Kirk that the source was about thirty meters higher than his present location . Thus , Kirk and Spock enter Seven ' s apartment building . The Beta 5 tells Seven that agents 201 and 347 were killed in an automobile accident ten miles north of McKinley Rocket Base on Highway 949 . Seven laments the uselessness of dying in such a manner and asks if the facts are verified . The computer does confirm this , noting that the description of the agent ' s bodies is accurate . On the floor outside Seven ' s apartment , Scott tells Kirk which way to go and they find the right apartment . Kirk rings the doorbell and Seven has the computer deactivated . Roberta opens the door , but when Kirk asks about Seven , she says that she has no idea who he is talking about , that this is a government office , and that they should leave immediately . But Kirk will have none of it , demanding to know where Seven is . Roberta demands that Kirk leave , but he refuses , and she finally grabs the phone and calls for the police . Kirk and Roberta briefly struggle over the phone and she asks Seven to come help her . Seven , meanwhile , has entered the transporter in his safe and disappeared . Spock discovers where Seven was , and Kirk goes in and has Spock restrain Roberta . She manages to pull Spock ' s cap off and is dumbstruck at the sight of Spock ' s pointed Vulcan ears . Seven rematerializes inside the rocket base and observes the rocket which is armed with the warhead . Act Three . Kirk finds Seven ' s map of McKinley Rocket Base . Roberta tells them she has already called the police to the office . When the police arrive , Spock tries to keep Roberta quiet , but she screams before he can . Kirk calls Scott , whom he orders to perform a wide scan , as they will be moving , and be ready to beam them up . They run into the office , but Roberta runs to the door , admits the police , and points them into the office . They run in just as Kirk orders them beamed up – and the two police officers are beamed up with Kirk and Spock , all four disappearing before Roberta ' s eyes . Kirk and Spock jump off the transporter platform , and Kirk immediately orders Scott to beam the policemen back down , which he does . The two policemen are returned to the office , leaving " them " dumbstruck at what they have seen and experienced and Roberta not knowing what to believe . At the rocket base , there are only fifty minutes until launch . Seven is approached by a security guard as he approaches launch control . The guard , Sergeant Lipton , has Seven lower Isis to the ground and requests identification , and Seven produces his CIA ID . While the guard calls to verify , Isis distracts Lipton , allowing Seven to stun him with his servo and he then takes the phone and tells the security identification office at the other end that everything is now OK . He then sits the stunned guard down and tells him to take a nap . Seven then makes his way to the gantry elevator by hiding in the trunk of the launch director ' s , Cromwell ' s , car . When the car arrives at the launch pad , he exits the trunk , hides in the elevator , reaches a gantry , removes an access panel with his servo and begins to rewire the rocket . Meanwhile , Kirk , Spock , and Scott , in the transporter room , search for Seven at the launch site by reflecting their sensors off a low - orbiting weather satellite . Unable to find him , Kirk and Spock decide to beam down to the base to search for Seven the old - fashioned way . They materialize in front of the previously stunned guard as he awakens . Lipton takes them into custody and escorts them to the control room in the launch complex . They are briefly interrogated , but all attention is focused on the launch preparations . Kirk and Spock stand there unable to act . Meanwhile , planning to quit again and telling the computer interface that she promises not to tell anyone about Seven or anything she has seen , Roberta accidentally discovers that depressing a pen holder on the desk opens the sliding glass rack . She then fiddles with the combination lock to the safe and succeeds in opening the safe / alien transporter room . At the same time , using the ship ' s sensors , Scott locates Seven on the rocket gantry while he is manipulating wires on the rocket . Scott calls for security and then attempts to beam Seven back aboard . Sensing the transporter beam , Seven gathers Isis into his arms . But at the same time , Lincoln ' s fiddling with the safe / alien transporter controls pulls him back to the NYC office . In the launch facility , Kirk and Spock watch helplessly as the countdown progresses . The security officers inspect Kirk ' s and Spock ' s phasers and communicators . The security supervisor tells Kirk that only the slightest possible charges will be brought against them if they explain why they are here and what they are doing . Kirk can only stand silently and watch as the rocket launches up toward space . Act Four . In the office , Seven is initially angry at Roberta for interfering , but he then calms down when he realizes that what she had done likely kept him from being transported back aboard the " Enterprise " and again taken prisoner . He then goes over and begins to work at the Beta 5 computer . He inquires whether he had done enough to take control of the rocket , and the Beta 5 confirms that he had . Seven uses the Beta 5 exceiver circuits to cause the third stage of the American rocket to malfunction and veer the rocket off course . He also arms the warhead and Roberta , who had become very suspicious of Seven , hits him on the head with a small jewelry box , for she now realizes that what he has been doing is beyond the CIA ' s abilities . She grabs Seven ' s servo and tells him to stay where he is . Seven begs Roberta to let him finish what he had started , otherwise when the rocket warhead detonates somewhere in six minutes , it will start World War III . From the science station on the bridge , Chekov and Sulu see the warhead arm and call Scott in the transporter room to inform him . Sulu tells Scott that the computers indicate an impact somewhere in the heart of the Eurasian landmass . Uhura , listening in to broadcasts from her station in multiple Earth languages , reports that she is receiving military alerts from the major powers . Scott decides that he will have to risk calling Kirk , and tells Uhura to open a channel to his communicator . At launch control , the mission planners note the malfunction in the rocket and try to override it and get it back on course . When the warhead arms itself , the scientists are confused as to how it could have done so on its own . They prepare to send a self - destruct signal to prevent the H - bomb from otherwise detonating on an unsuspecting population somewhere . Kirk , taking advantage of this distraction , steps over and tries to activate his communicator , but Lipton catches him and sends him back to his corner . Just then , Scott attempts to contact Kirk for instructions . When the communicator beeps and the rocket base guard picks it up and tries to talk to Scott , Spock steps over , under the guise of showing Lipton how to use it , and uses his nerve pinch to render him unconscious . Kirk has Scott beam them directly to Seven ' s office . Unfortunately for the scientists , the self - destruct signal does not work . The lead flight controller picks up a red phone to make a call to the President . Back in Seven ' s apartment , Seven tries to tell Roberta the truth about what has been happening and that truly advanced civilizations would neither take strange forms nor visit Earth in force , explaining that the best option is to bring Humans to their planet and train them for generations , until they are needed on Earth . Roberta tells him that she wants to believe him , for she knows that her world needs help ; this explains the seemingly insane conduct of some of the people of her generation , of whom she points out , " We wonder if we ' re gonna be alive when we ' re thirty . " Just as Seven tries to run back to the computer , Kirk and Spock enter . Kirk asks Spock if he can detonate the warhead using the computer , and the Vulcan says that he can attempt it . Seven says that he wants it detonated too and that " he " will have to do it , at least a hundred miles above the ground so that it will frighten the people of Earth out of the arms race . At that moment , Scott calls Kirk , telling him that the " Enterprise " s monitors show all major powers on full missile alert and a retaliatory strike is ordered upon warhead impact . Spock says that without more time , he can only estimate , and Seven angrily asks Kirk to allow him to do his job . Kirk insists that he still does " not " know what Seven ' s job " is " , and that for all he and Spock know , Seven may set the controls so that the warhead may not even be detonated . Then Roberta points the servo at Kirk and demands that he leave Seven alone . Seven quickly grabs it from her hand and tells her that the servo was set to kill . He deactivates it and then hands it over to Kirk . Kirk tells Spock if he cannot detonate the warhead , then they will both have to trust Seven . Spock tells Kirk that in the absence of facts , there is no logic al decision and that he will have to rely on his Human intuition to guide him . After a brief moment , Kirk tells Seven , " " Go ! " " Seven runs over to the Beta 5 and begins working the controls , activating a visual of low Earth orbit and having the computer count down the miles by tens . Finally , at 104 miles , Seven manages to detonate the warhead . A bit later , Seven is dictating the last bit of his report into the typewriter . " " . . . and in spite of the accidental interference with history by the Earth ship from the future , the mission was completed . " " Spock then corrects Seven and tells him that by all appearances they did not interfere but that , rather , that the " Enterprise " was simply part of what was supposed to happen on this day in 1968 . Kirk says that their record tapes show that while it was never generally revealed , a malfunctioning sub - orbital warhead was exploded exactly 104 miles above the Earth . Spock adds that , furthermore , it caused the nuclear powers to re - assess the risks of a nuclear orbiting platform . That everything turned out just how it was supposed to leaves Seven feeling relieved . For a moment , Roberta looks over at Isis and sees a rather gorgeous woman . She steps over to Seven and asks if he will explain who that is . Seven says that it is simply his cat . When Roberta looks back , Isis is a cat again . Seven then asks Kirk what else their record tapes show , but Kirk says they cannot , in turn , reveal all they know . Spock does say that it would be safe to say that Seven and Roberta have some interesting experiences ahead of them and Kirk agrees with that assessment . Kirk calls to be beamed up by Scotty , Spock tells Seven to " live long and prosper , " and Kirk says that the same goes for Roberta . They beam back aboard , and the " Enterprise " leaves orbit to go back to its proper time . Memorable quotes . " " Humans of the twentieth century do not go beaming around the galaxy , Mister Seven . " " " " It ' s impossible to hide a whole planet . " " " " Impossible for you , not for them . " " " " Mr . Spock , historical report . " " " " Current Earth crises would fill a tape bank , captain . " " " " Where ' s Three - Four - Seven ? " " " " With Three - Four - Eight ? " " " " Well , how do you expect me to type ? With my nose ? " " " " I ' m telling you , you ' re through monkeying around with my country ' s rocket . " " " " I know this world needs help . That ' s why some of my generation are kind of crazy and rebels , you know ? We wonder if we ' re gonna be alive when we ' re thirty . " " " " Without facts , the decision cannot be made logically . You must rely on your Human intuition . " " " " That , Miss Lincoln , is simply my cat . " " Links and references . References . 1968 ; 1978 ; 20th century ; Agent 201 ; Agent 347 ; Asia ; Assigners ' planet ; Bermuda ; Beta 5 computer ; birthmark ; " Bones " ; business suit ; Canary Islands ; cat ; Central Intelligence Agency ; class 1 supervisor ; coat rack ; code name ; colonel ; deflector shield s ; Department of Investigation ; dog ; Earth ; Earth Cold War ; East 68th Street ; encyclopedia ; Euro - Asian continent ; exceiver ; extended orbit ; Falcon ; Federal Bureau of Investigation ; feet ; force shield ; ; gantry ; H - bomb ; Highway 949 ; history ; ; Homicide Squad ; Human history ; hydrogen ; Identification card ; intelligence quotient ; IQ ; ; launch director ; light - speed breakaway factor ; logic ; McKinley Rocket Base ; meter ; mile ; Milky Way Galaxy ; minute ; missile ; mole ; National Security Agency ; New York City ; New York City Police Department ; nuclear holocaust ; nuclear weapon ; nuclear warhead platform ; Omicron IV ; orbit ; oxygen ; police ; pound ; Precinct 81 ; President of the United States ; record tapes ; rocket ; ; Saturn V ; ; sergeant ; servo ; ship ' s store ; smoking ; South Africa ; sub - orbital warhead ; subway ; Supervisor 194 ; tape bank ; telephone ; time travel ; transporter ; transwarp beaming ; typewriter ; United States of America ; USS ; voice pattern ; Vulcan ; Vulcan neck - pinch ; warhead ; weather satellite ; World War III