The 25 Most Memorable Episodes of Any Star Trek

The Naked Time (Star Trek: The Original Series, Season 1, Episode 4)

The Naked Time (Star Trek: The Original Series, Season 1, Episode 4)

A mysterious virus infects the crew, breaking down their inhibitions and letting their deepest fears and desires come to the forefront. Sulu runs around shirtless wielding a sword while Spock has an emotional meltdown.

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Arena (Star Trek: The Original Series, Season 1, Episode 18)

Arena (Star Trek: The Original Series, Season 1, Episode 18)

Captain Kirk beams down to a desert planet to fight a space lizard. This episode marks the first sighting of the Gorn and the first (but certainly not last) encounter filmed at the Vasquez Rocks in northern Los Angeles. It's also one of the first times the crew of the Enterprise wrestles with the concept that maybe the Federation got something wrong -- a moral dilemma the show would revisit in every series.

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The Changeling (Star Trek: The Original Series, Season 2, Episode 3)

The Changeling (Star Trek: The Original Series, Season 2, Episode 3)

A space probe named Nomad vaporizes security guards, attacks nurses, and reads sensitive HR personnel files with impunity until Captain Kirk puts a stop to it. He comes to the rescue with an infinite logical loop that forces the computer to break down.

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The Trouble with Tribbles (Star Trek: The Original Series, Season 2, Episode 15)

The Trouble with Tribbles (Star Trek: The Original Series, Season 2, Episode 15)

Captain Kirk finds himself and the crew up to their eyeballs in adorable (but dangerous!) little floof balls. Possibly the greatest episode of any show ever. It scored three Emmy nominations and a follow-up episode in Star Trek: Deep Space Nine's "Trials and Tribble-ations." 

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A Piece of the Action (Star Trek: The Original Series, Season 2, Episode 17)

A Piece of the Action (Star Trek: The Original Series, Season 2, Episode 17)

In order to avoid violating the Prime Directive, Captain Kirk and Spock have to visit a planet dressed up like 1920s gangsters with Tommy guns. It turns out the entire society is based on a book about Chicago mob culture. Kirk distracts their captors with a made-up card game called "Fizzbin" while the crew escapes.

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Encounter at Farpoint  (Star Trek: The Next Generation, Season 1, Episode 1)

Encounter at Farpoint (Star Trek: The Next Generation, Season 1, Episode 1)

This is the very first episode of Star Trek: The Next Generation -- affectionately called TNG -- and the first one where we meet Q, a recurring antagonist. All of the Q episodes are really, really great. In this one, he insists on putting all of humanity on trial. This episode also marks the first appeerance of the man-skant. 

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Elementary, Dear Data (Star Trek: The Next Generation, Season 2, Episode 3)

Elementary, Dear Data (Star Trek: The Next Generation, Season 2, Episode 3)

TNG starred Patrick Stewart leading the crew of the Enterprise as Captain Jean-Luc Picard. Instead of half-human Spock, fully functional android and Chief Operations Officer Data plays the part of the outsider puzzled by emotions. In this episode, Data and Geordi La Forge challenge the ship's holodeck to create a unique Sherlock Holmes mystery that Data can't solve.

Naturally, the holodeck simulation of Professor Moriarty instantly gains sentience and tries to take over the Enterprise. (In a later episode, "Ship in a Bottle," Moriarty makes himself a simulated girlfriend and demands to be released from the holodeck.) This episode continues the grand tradition of putting the Enterprise crew in period garb; in this case, they go full Victorian London.

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The Measure of a Man (Star Trek: The Next Generation, Season 2, Episode 9)

The Measure of a Man (Star Trek: The Next Generation, Season 2, Episode 9)

Commander Bruce Maddox, a cyberneticist, boards the Enterprise under the guise of asking Data a few questions about his creator. It turns out Maddox wants to dismantle Data and upload his memory to the starbase mainframe in order to figure out how to recreate his positronic brain.

Data resigns from Starfleet to avoid being disassembled, at which point Maddox claims he is Starfleet property, not a sentient being who can decline orders. Picard demands a formal hearing to determine whether Data has a soul.

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Yesterday's Enterprise (Star Trek: The Next Generation, Season 3, Episode 15)

Yesterday's Enterprise (Star Trek: The Next Generation, Season 3, Episode 15)

Another standout time-travel episode. An Enterprise ship and crew from an alternate timeline come through a temporal rift. Coincidentally, this crew comes from a time when the Federation is at war with the Klingons. Captain Picard and his crew have to decide whether to send them back to their near-certain demise or risk disrupting their own timeline. Denise Crosby, whose character Tasha Yar was killed in Season 1, makes a comeback as a member of the alternate-timeline Enterprise crew.

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The Best of Both Worlds (Star Trek: The Next Generation, Season 3, Episode 26 and Season 4, Episode 1)

The Best of Both Worlds (Star Trek: The Next Generation, Season 3, Episode 26 and Season 4, Episode 1)

Captain Picard gets assimilated into the Borg collective after investigating a vanished Federation colony. This one is widely cited as not only one of the best Star Trek episodes of all time, but one of the best episodes of any TV series of all time, and won Emmys for art direction and sound editing.

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Family (Star Trek: The Next Generation, Season 4, Episode 2)

Family (Star Trek: The Next Generation, Season 4, Episode 2)

After defeating the Borg and de-assimilating Captain Picard, the ship is in dry dock for repairs as the crew heads to Earth for shore leave and family visits. Beverly Crusher retrieves a holographic message from her late husband to give to their son Wesley, Worf spends time with his Russian human adoptive parents, and Picard gets drunk with his brother in the family's vineyard in France.

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The Inner Light (Star Trek: The Next Generation, Season 5, Episode 25)

The Inner Light (Star Trek: The Next Generation, Season 5, Episode 25)

A mysterious probe blasts Picard with an energy beam, which knocks him unconscious. When he wakes up, he's Kamin, an iron weaver on the non-Federation planet Kataan. Picard lives for decades as Kamin, starting a family with his wife Eline (including a son played by Patrick Stewart's actual son, Daniel), spending time in nature, and learning to play the flute. He and his daughter investigate a drought on their planet that threatens all life there.

Back on the Enterprise, only a few minutes pass while the crew tries to revive Picard.

We don't want to spoil the ending of this one for people who haven't seen it. Patrick Stewart once said that this is his favorite episode.

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Time's Arrow Part. I & II (Star Trek: The Next Generation, Season 5, Episode 26 and Season 6, Episode 1)

Time's Arrow Part. I & II (Star Trek: The Next Generation, Season 5, Episode 26 and Season 6, Episode 1)

There's a lot to say about this two-part episode, which won two Creative Arts Emmys. Time travel was a recurring theme in all the series. In this case, Data went back to 1893, where he met Mark Twain, Jack London, and a younger version of Whoopi Goldberg's character, Guinan. They discover aliens are taking advantage of a cholera outbreak to steal life forces and dilate time. An Enterprise away team goes back in time to save Data using his severed head -- right, we should have mentioned, they found Data's severed head in a cave at the beginning of the episode -- to communicate 500 years back and forth in time.

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Chain of Command Part I & II (Star Trek: The Next Generation, Season 6, Episodes 10 and 11)

Chain of Command Part I & II (Star Trek: The Next Generation, Season 6, Episodes 10 and 11)

This is technically a two-part episode, but most fans agree you can start on Part II and just pay close attention to the "Previously on…" section. Picard, Worf, and Beverly Crusher investigate what they think is a Cardassian biological weapon. It turns out it was a trap, and Picard is physically and psychologically tortured and interrogated. When people reference the "There are FOUR lights!" episode, it's this one.

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Duet (Star Trek: Deep Space Nine, Season 1, Episode 19)

Duet (Star Trek: Deep Space Nine, Season 1, Episode 19)

Major Kira Nerys realizes that a passenger who came to Deep Space Nine to be treated for a rare disease was, years earlier, involved with the occupation of her planet. She has to figure out who he really is -- and then figure out what's going on when he suddenly admits to being a war criminal who slaughtered thousands of her people. Ultimately, she realizes she has to re-examine her prejudices about the Cardassians.

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Trials and Tribble-ations (Star Trek: Deep Space Nine, Season 5, Episode 6)

Trials and Tribble-ations (Star Trek: Deep Space Nine, Season 5, Episode 6)

Remember the tribble episode from the original series? It was so beloved that DS9 gave it a sequel.

In the episode, the DS9 crew has to travel through time to prevent a Klingon from murdering Captain Kirk with a booby-trapped tribble. The show used digital imaging to insert characters into the original tribbles episode and recreated the sets and costumes from the original series. The episode was nominated for three Emmys and brought back a number of original cast members both onscreen and behind the scenes. 

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Far Beyond the Stars (Star Trek: Deep Space Nine, Season 6, Episode 13)

Far Beyond the Stars (Star Trek: Deep Space Nine, Season 6, Episode 13)

Captain Benjamin Sisko is considering leaving Starfleet when he's confronted by visions of himself as a twentieth-century writer, named Benny Russell. In his vision, Russell confronts racism as a black science fiction writer in New York City in the 1950s. The entire crew plays different roles in the vision, including Kira Nerys as a female writer hiding behind a pen name to avoid sexism and Odo as the racist publisher of the magazine where Benny Russell works. This episode plays with three of Star Trek's favorite themes: Time travel, alternate universes, and putting the whole cast in costumes.

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In the Pale Moonlight (Star Trek: Deep Space Nine, Season 6, Episode 19)

In the Pale Moonlight (Star Trek: Deep Space Nine, Season 6, Episode 19)

Captain Sisko recognizes that the Federation's war with the Dominion is costing them both money and lives. To tip the scales in Starfleet's favor, Sisko hatches a plan to persuade the neutral Romulans to join their side. He works with a former Cardassian spy and enlists the help of a criminal forger to create "evidence" that the Dominion is planning on attacking the Romulans. Things don't work out exactly the way Sisko wants them to, and he is forced to reconcile his and Starfleet's values versus the true cost of winning the war.

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Take Me Out to the Holosuite (Star Trek: Deep Space Nine, Season 7, Episode 4)

Take Me Out to the Holosuite (Star Trek: Deep Space Nine, Season 7, Episode 4)

Ever wondered who would win in a baseball game of Vulcans versus humans? Wonder no more! Captain Sisko runs into an old rival on Deep Space Nine, and they agree to a showdown to prove which race is truly superior. Sisko has two weeks to train his crew to play holo-baseball, and obviously takes it all way too seriously.

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The Thaw (Star Trek: Voyager, Season 2, Episode 23)

The Thaw (Star Trek: Voyager, Season 2, Episode 23)

Voyager finds a set of five stasis pods on a deserted planet. Two of the stasis pod occupants are dead; the other three can't be awoken. Kim and Torres go into the two pods and connect themselves to the central computer, where they discover a program has taken the form of a clown and is torturing the remaining three stasis captives in a hologram of their fears. The Doctor has to enter the simulation to try to persuade the program to let its hostages go.

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Year of Hell, Part I & II (Star Trek: Voyager, Season 4, Episodes 8 and 9)

Year of Hell, Part I & II (Star Trek: Voyager, Season 4, Episodes 8 and 9)

The crew of Voyager is negotiating with the Zahl when a Krenim ship begins attacking them. Captain Kathryn Janeway ignores the small ship; suddenly, a temporal blast hits all three ships, leaving the Zahl vaporized, Voyager severely damaged, and the Krenim ship larger and more powerful. It turns out the Krenim have a time-shifting weapon that deletes events from history that inconvenience them. Janeway has to figure out a way to use their time weapons against them while keeping her crew safe.

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Living Witness (Star Trek: Voyager, Season 4, Episode 23)

Living Witness (Star Trek: Voyager, Season 4, Episode 23)

An encounter between Voyager and the Kyrians is seen from the Kyrians' point of view -- 700 years in the future. In a Kyrian museum recreation of what happened, Voyager crew are all sadistic mass murderers, depicted as caricatures of themselves. The museum curator discovers a way to reactivate Voyager's holographic Doctor, who insists on setting the record straight.

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Carbon Creek (Star Trek: Enterprise, Season 2, Episode 2)

Carbon Creek (Star Trek: Enterprise, Season 2, Episode 2)

Sub-Commander T'Pol reveals that the first contact between humans and Vulcans actually took place a century earlier than the historical record shows. T'Pol tells the story of her great-grandmother, T'Mir, who crash-landed on Earth in the 1950s and lived with two other Vulcans in a Pennsylvania mining town called Carbon Creek.

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Similitude (Star Trek: Enterprise, Season 3, Episode 10)

Similitude (Star Trek: Enterprise, Season 3, Episode 10)

Commander Charles "Trip" Tucker is left in a coma after an explosion while he's working on the warp drive. Doctor Phlox suggests that the only way to save him is to clone him with a "mimetic symbiote." Captain Jonathan Archer is hesitant but ultimately goes forward with the plan when he accepts that the ship is in danger. The clone will only live for 15 days, and Phlox can harvest neural tissue from it to bring Tucker back to life. However, the clone -- named Sim -- learns what he is and what his fate will be, and he and the entire crew have to decide how to proceed.

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In a Mirror, Darkly, Part I & II (Star Trek: Enterprise, Season 4, Episodes 18 and 19)

In a Mirror, Darkly, Part I & II (Star Trek: Enterprise, Season 4, Episodes 18 and 19)

These two episodes take place in a mirror universe. An evil version of Commander Archer mutinies against Maxwell Forrest, who was captain of the Enterprise in that universe, and the crew goes into Tholian space to capture a Starfleet ship from the future. The events of these episodes are a sequel to "The Tholian Web" from the original series.

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