Summary
Time travel has served as a recurring theme inStar Treksince the classic original series. Introductions to time travel have varied from series to series, with everything from advanced technology to bizarre, natural phenomena setting it up.
In theStar Trekuniverse, time travel has been pulled off via everything from temporal rifts, to slingshot effects around celestial bodies,to advanced powers such as the Guardian of Forever. A common narrative trait across the franchise when it comes to time travel is the exploration of its consequences. These include inadvertently creating alternate timelines, changing important historical events, and the risks of encountering past or future versions of series characters. Of the many time travel episodes over the decades, a select few stand out from the rest.

5Time’s Arrow Sends The Crew Back To The 19th Century
IMDB Rating: Part 1 - 8.3/Part 2 - 8.2
This famed two-parter kicks off on a strange notewhen it appears that Data may have been around in 19th-century San Francisco. Intrigued, the crew travels back through time to investigate.
There’s a neatly balanced blend of humorand mystery on offer here, as the crew navigate both the challenges of time travel and of living in a completely different period. With some surprise appearances from historical figures of the day, the colorful plotline keeps viewers on their toes with its unpredictability. The second part takes viewers further into the mystery aspects of the plot, showcasing the series writers' knack for heady, complicated mysteries and big reveals. Overall, it’s a fun showcase of the offbeat storytelling that madeThe Next Generationso special.

4Year Of Hell Is A Tragic Epic
IMDB Rating: Part 1 - 8.7/Part 2 - 8.6
This thrilling two-parter sees the crew collide with a powerful adversary who can control time itself. A dangerous temporal manipulator named Annorax intends to create a year of perpetual warfare and destruction.
Trapped in this hellish altered reality, the crew’s wits and resolve are put to the test as they face their darkest challenges yet. At one point planned to cover a whole season ofVoyager, this dramatic epic provides some surprisingly poignant notes in among the apocalyptic thrills. The Annorax character proves to be far more complex than a standard villain, as viewers discover he’s haunted by accidentally causing the tragic death of his beloved wife. With a compelling look at time alteration, plenty of ringers for theVoyagercrew to endure, and a memorable antagonist, “Year of Hell” was afine chapter inVoyager’s celebrated run.

3The City On The Edge Of Forever Was A Seminal Moment In Television History
IMDB Rating: 9.2
This classic episodefrom the first season ofThe Original Seriessees Captain Kirk and Spock forced to travel back to the 1930s. A catastrophic change in history forms the centerpiece of this seminal chapter in the long-running franchise.
The episode quickly descends into chaos when McCoy travels back in time via The Guardian of Forever and winds up inadvertently causing a timeline in which the Federation of Planets never comes to be. To save the day, Kirk and Spock must go where McCoy went in time, and undo the disaster his mishap led to. Widely considered a landmark moment forStar Trekand television as a whole, this seminal piece of high-stakes time travel drama manages to serve as both a fascinating piece of sci-fi existentialist storytelling and a surprisingly emotional thrill ride with a powerfully tragic climax.

2Yesterday’s Enterprise Is A Dramatic Study Of The Perils Of Time Travel
This thrilling entryin the belovedNext Generationseriessees the crew encounter a rift in space-time. Through it there lies an alternate timeline in which the Federation is now at all-out war with the Klingon Empire.
Exploring complex themes of duty and sacrifice, viewers follow the crew as they grapple with the dangerous consequences of altering the past. This third-season entry was an immediate hit with fans and critics alike, with many highlighting its high-stakes plot and fast pace as key areas worthy of praise. The surprise return of Tasha Yar - who was infamously killed off in a polarizing fashion back in Season 1 - also leads to some of the third season’s strongest writing, as her brief but powerful arc emphasizesthe grim importance self-sacrifice can play in heroism. Overall, it’s one ofThe Next Generation’s most thought-provoking and layered episodes.

1Trials And Tribble-ations Is A Witty Trip Down Memory Lane
IMDB Rating: 9.3
In a more light-hearted example of time travel in theStar Trekseries, this episode takes viewers back to a much earlier chapter in the franchise. TheDeep Space Nineteam finds themselves in the period of the humorous “The Trouble With Tribbles” from Season 2 ofThe Original Series.
The original episode saw the Enterprise visit a space station that gets overrunwith tribbles, fast-breeding furry animals. A hit with viewers at the time, the creatures get an update inDeep Space Nine, as it’s revealed that they’re one of the many speciesto have issues with the ever-dangerous Klingons. Cleverly blending new series footage with scenes from the original show, “Trials and Tribble-ations” is a cleverly composed piece of both nostalgia and original storytelling. With an unpredictable bomb-focused plot and a mountain of clever references, this is a fine example of time travel done right in theStar Trekfranchise.
