Star Trek‘s most important time travelers have made a lasting impact on the Star Trek timeline. Time itself is a different kind of final frontier for Star Trek characters, so time travel stories have been a staple of Star Trek since the beginning of the franchise. Temporal anomalies, chroniton particles, Klingon time crystals, and encounters with all-powerful beings like Q (John de Lancie) can send characters all over the Star Trek timeline. Intentional time travel is also possible with the slingshot effect perfected by Captain James T. Kirk (William Shatner) and the USS Enterprise crew in Star Trek: The Original Series, and the Federation’s own technology in the 31st century.

Before time travel becomes commonplace in Star Trek‘s future, it’s still considered incredibly risky, and the Vulcans even consider it “unfair,” according to Star Trek: Enterprise‘s Subcommander T’Pol (Jolene Blalock). When time travel does become as convenient as warp drive, the ability to alter history in any one faction’s favor creates the conditions of Star Trek‘s Temporal Cold War, which inadvertently makes time a relatively malleable construct. To that end, most of Star Trek‘s important time travelers take on desperately high stakes, where time travel is often the only answer to save the Federation, the people of Earth, or even all sentient life in the galaxy.

10

Admiral Kathryn Janeway

Star Trek: Voyager Season 7, Episodes 25 & 26 – “Endgame”

In an alternate future, the USS Voyager’s journey back to the Alpha Quadrant is not without terrible hardship, so Vice Admiral Kathryn Janeway (Kate Mulgrew) discovers a way to bring the USS Voyager home much sooner, avoiding over 22 casualties and Lt. Commander Tuvok’s (Tim Russ) slow mental decline. With a stolen Klingon Chrono-deflector, Admiral Janeway returns to her own past to provide Captain Janeway with future technology designed to succeed in a battle against the Borg, which will give the USS Voyager access to a Borg transwarp hub, and a near-immediate way home.

Admiral and Captain Janeway manage a compromise that will satisfy both of them. Admiral Janeway’s wish for Voyager’s faster return is granted when the Captain agrees to use the hub to get home, and Captain Janeway’s desire to destroy the hub is fulfilled when Admiral Janeway infects herself with a neurolytic pathogen before sacrificing herself to the Borg, who assimilate the pathogen. Admiral Janeway’s sacrifice in Star Trek: Voyager’s series finale keeps the Alpha Quadrant Borg-free for decades.

9

Lt. La’an Noonien-Singh (Christina Chong)

Star Trek: Strange New Worlds Season 2, Episode 3 – “Tomorrow and Tomorrow and Tomorrow”

In Star Trek: Strange New Worlds season 2, episode 3, “Tomorrow and Tomorrow and Tomorrow”, Lt. La’an Noonien-Singh is handpicked by a dying Federation time agent (Christopher Wyllie) to complete an important mission that ensures the preservation of Star Trek‘s Prime timeline. Before heading back to the past, however, Lt. Noonien-Singh is transported to an alternate timeline where Starfleet is at war, and accidentally takes the United Earth Fleet Enterprise’s Captain James T. Kirk (Paul Wesley) with her to the early 21st century.

La’an and Jim’s love story is pivotal to La’an’s character growth in Strange New Worlds, but La’an’s greater impact on the overall timeline comes after discovering Sera (Adelaide Kane), a time-traveling Romulan, is also in 21st century Toronto. Sera intends to kill a young Khan Noonien-Singh (Desmond Sivan) and prevent the rise of the Federation, but La’an takes matters into her own hands to thwart the Romulan plot after Sera kills Kirk in cold blood. Lieutenant Noonien-Singh’s key mission shakes La’an to her core, but is ultimately a success for the Federation.

8

Admiral Jean-Luc Picard (Patrick Stewart) & La Sirena Crew

Star Trek: Picard Season 2

In 2401, a dying Q asks for help from Admiral Jean-Luc Picard (Patrick Stewart) to correct the mistakes that Q made in the past. With his power reserves depleting, Q transports Picard into an alternate timeline, where Earth is ruled by the xenophobic Confederation, in a complete reversal from the hopeful Federation that Picard knows well. From their alternate present, Picard and the La Sirena crew travel back to 2024 Los Angeles, where they have to prevent the incident that altered the timeline.

Jean-Luc Picard has to make sure that his ancestor, Renée Picard (Penelope Mitchell), launches a historic mission to Europa, despite past Q meddling and the alternate timeline’s Borg Queen (Annie Wersching) trying to reconstruct her Borg Collective in the 21st century. Renee Picard’s mission becomes a load-bearing event in constructing the hopeful timeline of Star Trek‘s future, in addition to being an important part of Jean-Luc’s own history, so Picard’s involvement is instrumental.

7

Admiral James T. Kirk (William Shatner) & the USS Enterprise Crew

Star Trek IV: The Voyage Home

When a mysterious probe shuts down everything in its path and threatens to destroy Earth unless it can communicate with long-extinct humpback whales, Admiral James T. Kirk (William Shatner) and the USS Enterprise crew must go back to a time before the whales’ extinction. Spock (Leonard Nimoy) makes the calculations to use a slingshot effect that takes the crew’s stolen Klingon bird-of-prey, renamed the USS Bounty, back to the 20th century. There, marine biologist Dr. Gillian Taylor (Catherine Hicks) helps Kirk and Spock by introducing them to two of her whales, George and Gracie.

The danger to Earth that precipitates Admiral Kirk and his crew’s journey through time is underscored in Star Trek IV: The Voyage Home, which shines as a comedic time-travel story that sees the Enterprise crew interact with the then-present 1980s. Spock’s idea to physically retrieve the humpback whales from the past ensures the survival of Earth in the 23rd century, since there was no other way to call off the powerful probe.

6

Captain Benjamin Sisko (Avery Brooks) & The DS9 Crew

Star Trek: Deep Space Nine Season 5, Episode 6 – “Trials and Tribble-ations”

With the Bajoran Orb of Time aboard the USS Defiant, Captain Benjamin Sisko (Avery Brooks) and the Star Trek: Deep Space Nine crew find themselves nearly a century in the past, at Space Station K-7 with Kirk’s USS Enterprise. While trying to find a way back to their own time, Sisko’s crew discover Klingon Arne Darvin (Charlie Brill) means to kill Captain James T. Kirk with an explosive tribble, and search through the rapidly multiplying critters to find and disarm the bomb. Although the trip back in time seems accidental, the Prophets work in mysterious ways, suggesting that Sisko’s crew were always present to ensure Kirk’s safety in the 23rd century.

5

Captain Chakotay (Robert Beltran)

Star Trek: Prodigy

On a return mission to the Delta Quadrant, Captain Chakotay (Robert Beltran) and the original crew of the USS Protostar were pulled into a temporal anomaly that opened above the planet Solum in the 25th century. Solum had suffered a bloody civil war resulting from the planet’s First Contact with Starfleet, which had occurred between the time Chakotay left and the Protostar’s arrival. The people of Solum, the Vau N’Akat, called for vengeance on Starfleet, and installed a weapon called the Living Construct on the USS Protostar, which would destroy Starfleet from the inside. Rather than endanger Starfleet, Chakotay sends the Protostar back in time, kicking off the events of Star Trek: Prodigy.

4

Captain Jean-Luc Picard & USS Enterprise Crew

Star Trek: First Contact

Against Starfleet’s orders, Captain Jean-Luc Picard (Patrick Stewart) elects to engage the Borg near Earth, and follows a Borg Sphere through a temporal vortex to 2063, just days before humanity’s first warp flight and subsequent contact with the Vulcans. With the intent of assimilating Earth in the past, the Borg pose an existential threat, and Picard reckons with the trauma that feeds his singleminded vengeance against the Borg. Commander William Riker (Jonathan Frakes) leads the away team in Montana that helps Zefram Cochrane (James Cromwell) to keep history’s historic warp flight on track. Both storylines in Star Trek: First Contact are integral to the survival of Earth.

3

Commander Michael Burnham

Star Trek: Discovery Season 2 & 3

The Red Angel in Star Trek: Discovery season 2 creates a compelling mystery for the USS Discovery crew to decode. The bursts of red light signal important people and places for the Discovery to visit and gather resources to battle against Section 31’s Control A.I. before Control goes rogue and eliminates all sentient life in the galaxy. The stakes are high, but Commander Michael Burnham (Sonequa Martin-Green) is dedicated to the mission that Burnham is destined to undertake — even when Burnham must lead Discovery 900 years into the future to win against Control.

Commander Burnham’s actions as the Red Angel are important, but Burnham has the most impact on the Star Trek universe in the 32nd century. Being relics of the 23rd century gives the Discovery crew a unique perspective, and Burnham embraces the chance to show the future that reconnection is possible after the Burn devastated interstellar travel. Starfleet begins to rebuild in a brighter future that wouldn’t have been possible without Discovery’s reminder of Starfleet’s heyday and Michael Burnham’s optimistic convictions.

2

Ambassador Spock (Leonard Nimoy)

Star Trek (2009)

Ambassador Spock (Leonard Nimoy) intended to use red matter to create a singularity that would prevent the destruction of Romulus in the 2387 Romulan supernova. Too late to save Romulus, Spock creates a red matter black hole to stymie the supernova’s further damage, which pulls Spock back in time to 2258. Spock is pursued by a surviving Romulan captain, Nero (Eric Bana), who swears vengeance on Ambassador Spock for failing to save Romulus. Nero’s actions in the past create an alternate reality, where history plays out much differently from Spock’s memories.

Unable to return to the future or the Prime Timeline, Spock helps the USS Enterprise crew in the Kelvin Timeline when it’s logical to do so, and becomes a mentor to the younger Spock (Zachary Quinto). Ambassador Spock lives the rest of his life in the Kelvin Timeline that he is ultimately responsible for creating, and which continues on after his death.

1

Agent Daniels (Matt Winston)

Star Trek: Enterprise

Star Trek: Enterprise‘s Agent Daniels hails from the 31st century, when time travel has become common enough to be weaponized, and the Temporal Cold War is well underway. At least once a season, the ever-secretive Daniels appears to Captain Jonathan Archer (Scott Bakula) with missions designed to keep the Federation’s enemies from playing havoc with the timeline. Federation time travel technology protects Daniels’ life after his apparent death, as well as Daniels’ knowledge of the future, which remains intact despite the Cold War’s temporal incursions.

As an agent dedicated to preserving the United Federation of Planets, Agent Daniels’ importance to the timeline can’t be understated. Daniels takes Archer with him to the USS Enterprise-J in the 26th century, revealing the impact that Archer’s present actions have on the future. When Daniels himself can’t take the mission, Daniels enlists Archer’s help instead. Each of Agent Daniels’ Star Trek: Enterprise stories has the same goal of making sure Star Trek‘s United Federation of Planets doesn’t cease to exist.