Throughout 42 seasons of television and 13 movies, many familiar faces have populated the universe of "Star Trek." Some of the most surprising had only seconds of screen time, while others were dependable players with recurring parts or multiple roles. With its vast and decades-long fandom, it should come as no surprise that many of these actors, musicians, and entertainers leaped at the chance to be a part of the brainy adventures taking place across "Trek's" diverse quadrants.

This is just a small sampling. Nevertheless, here is a list of some of the more mind-blowing celebrities to play in "Trek's" sandbox. Though you won't find them in this article, even more recognizable faces frequented the world of "Trek," so special recognition goes to the likes of character actors Jeffrey Combs, William Sadler, and Kurtwood Smith. If you forgot that any of these performers made "Star Trek'' appearances, you'd be easily forgiven — there's an awful lot of "Trek" out there to sink your teeth into.

Jason Alexander

George Constanza on "Star Trek?" Yes, this really happened. "Seinfeld" actor Jason Alexander made his Trek debut in 1999 as the alien Kurros in the "Star Trek: Voyager" Season 5 episode "Think Tank." Kurros was a mullet-rocking humanoid scientist with elaborate forehead prosthetics typical of the Trek aesthetic. Kurros leads a group of diverse intergalactic problem solvers who attempt to aid Captain Janeway (Kate Mulgrew) and her crew in dealing with a race of bounty hunters known as the Hazari.

As often transpires in "Trek" narratives, Kurros is revealed to have ulterior motives behind his brainy, good samaritan facade. Alexander identifies as a lifelong Trekkie (or "Trekker," the preferred sobriquet of die-hards). He explained his fandom to StarTrek.com, stating, "It was the dedication to use the genre to explore the social issues of the day in dramatic form. There was always humor and poetry in the writing of Trekisodes." He went on to reveal that for his audition to study theater at Boston University, he drew inspiration from William Shatner for his monologues, as Captain Kirk is his favorite "Star Trek" character.

Christopher Lloyd

Christopher Lloyd's Klingon Commander Kruge has a special place in "Trek" lore. In "Star Trek III: The Search for Spock," the villainous Kruge is responsible for the death of James Kirk's son. David Marcus. This had reverberations throughout the saga of the original series cast, most notably in "Star Trek VI: The Undiscovered Country" in which Kirk's anger over his son's murder has curdled into a deeply felt xenophobia against the Klingon race. Kruge's dastardliness doesn't stop at homicide. His tactics force Kirk into engaging the Enterprise's self-destruct protocol, resulting in the first-ever on-screen annihilation of the iconic vessel.

Explaining his motivation for taking the role, Lloyd told Pop Goes the Culture TV, "He was just so deliciously evil ... I had no conscience ... and it made it a lot of fun" and that he relished the opportunity to use the Klingon language. The crew of Kruge's Bird of Prey also features another face familiar to fans of '80s pop culture. More on him later.

Christopher Plummer

Another iconic Christopher made an appearance as a Klingon in the "Trek" universe: 2012 Academy Award winner Christopher Plummer. Plummer played the role of Chang "Star Trek VI: The Undiscovered Country," a nefarious eyepatch-sporting general from the Klingon homeworld of Qo'nos. Ever the estimable thespian, Plummer makes a meal out of his time on screen in Nicholas Meyer's 1991 film (the third he penned in the franchise, and his return to the director's chair after "Star Trek II: The Wrath of Khan." Recently, Meyer has been a contributor to "Star Trek: Discovery" on Paramount+). Chang proves to be a worthy adversary to James T. Kirk and the crew of the Enterprise, attempting to implicate Kirk in the assassination of Klingon emissary Gorkon (David Warner, who would later show up as a Cardassian on "Star Trek: The Next Generation").

A known bookworm and history geek, Meyer gifted Warner with one of the all-time great lines of "Star Trek" dialogue: "You have not experienced Shakespeare until you have read him in the original Klingon," and Plummer follows suit by quoting "The Tempest" and "Julius Caesar" in his parting moments.

Kelsey Grammer

"Hey baby, I hear the Borgs a-callin'..." Yes, even Dr. Frasier Crane made his way to the set of "Star Trek: The Next Generation." Another sitcom performer making his way to Roddenberry's optimistic future, the estimable Kelsey Grammer lent gravitas to his appearance as Starfleet Capt. Morgan Bateson in the fifth season episode "Cause and Effect," which stands as one of "Star Trek: The Next Generation's" finest hours.

The plot concerns yet another temporal anomaly in which the Enterprise is trapped in a time loop where it perishes over and over. It's a classically brainy "Next Generation" episode that exalts the power of the human intellect. Grammar's Bateson captains the USS Bozeman, a time-displaced Starfleet vessel from 90 years before (hence Grammer is working his magic in the nautical ruby "Wrath of Khan"-era uniform). Another fun "Frasier"-"Star Trek" crossover is a skit from the 1996 "Star Trek: 30 Years and Beyond" broadcast, which features Kate Mulgrew and the cast of the NBC comedy with Grammer dropping by as a grumpy Klingon.

Iman

Needless to say, the cast of "Star Trek VI: The Undiscovered Country" is interesting. In addition to Plummer and Kurtwood Smith, Kim Catrall plays a pivotal role, and Lieutenant Worf himself, Michael Dorn, has a cameo. Iman, the supermodel (and widow to rock star David Bowie), appears as Martia, a Chameloid prisoner at the Klingon penal colony of Rura Penthe.

Martia's inclusion in the film marks a milestone in "Trek" continuity. For only the second time, an alien race was depicted as capable of shapeshifting (following the original series episode "Whom Gods Destroy"), years before "Star Trek: The Next Generation's" Devidians, "Star Trek: Enterprise's" Dee'Ahns, Wraith, and, most notably, the Changelings-Founders of "Star Trek: Deep Space Nine." The shapeshifting effect is a prominent example of the then-nascent morphing CGI pioneered by Industrial Light and Magic, which was also on display in that same year's classic "Terminator 2: Judgment Day."

Seth MacFarlane

Years before he created his farcical "Star Trek" homage "The Orville," "Family Guy" funnyman Seth MacFarlane appeared in two episodes of "Star Trek: Enterprise" ("The Forgotten" and "Affliction") as Starfleet officer Stewart Rivers.

Over the years MacFarlane has made no secret of his "Star Trek" fandom. "Family Guy" included multiple references to the franchise, even going so far as to bring aboard Trek alumni like Patrick Stewart, René Auberjonois (constable Odo on "Star Trek: Deep Space Nine"), and Majel Barrett (nurse Christine Chapel, Lwaxana Troi, and the voice of the Starfleet computers). In a recent blu-ray rerelease of "Star Trek: The Next Generation's" fifth season, MacFarlane joined TNG writer (and "The Orville" Executive Producer) Brannon Braga for an audio commentary on the aforementioned episode, "Cause and Effect." MacFarlane also called in a favor from William Shatner to reprise his role as Captain James T. Kirk for a sketch that opened his abysmal stint hosting the 85th Annual Academy Awards.

Adam Scott

Adam Scott of "Severance," "Big Little Lies," and "Parks and Recreation" fame has a blink-and-you'll-miss-it cameo in "Star Trek: First Contact'' as a helmsman aboard the USS Defiant. The ship featured prominently in "Star Trek: Deep Space Nine," which was airing simultaneously with the release of Jonathan Frakes' film (Hence, it's still intact. In the show, it ends up destroyed at the hands of the Breen during the Second Battle of Chin'toka).

When asked if there was one character from his storied career that he'd like to return to, Scott freely admitted it was his unnamed Defiant officer. His return to the Starfleet uniform would have to be, as Scott points out, a prequel, as his character dies in "Star Trek: First Contact" after his fleeting appearance. "We'll set it five years prior, so the film could be at most five hours long," Scott joked to Moviefone with his "Hot Tub Time Machine 2" co-stars Rob Corddry and Clark Duke.

John Larroquette

John Larroquette is probably best remembered for his role in the long-running legal comedy "Night Court." In addition to roles in "The Practice" and "Boston Legal," he also provided the opening narration for 1974's "Texas Chain Saw Massacre," its 2003 remake, and the 2022 legacy sequel. But did you know he played a Klingon soldier alongside the aforementioned Christopher Lloyd?

In 1984's "Star Trek III: The Search for Spock," Laroquette plays the unusually named (even by Klingon standards) Officer Maltz. The character doesn't have many lines in the film, and modern viewers would be forgiven for not recognizing the actor under his heavy alien prosthetics. He's borderline indistinguishable from fellow Bird of Prey crewmate Torg (Stephen Liska). At the time, Larroquette had only just begun his starring role as Dan Fielding on "Night Court." In the decades since, Larroquette has expressed fondness and an impish sense of humor about his participation in "Trek." 

Iggy Pop

Legendary punk rocker Iggy Pop made his Trek debut in the uproarious "Star Trek: Deep Space Nine" episode "The Magnificent Ferengi." In the standalone farce, Iggy Pop plays the conniving Vorta Yelgrun who kidnaps Ishka (Cecily Adams), mother to Quark (Armin Shimerman) and Rom (Max Grodénchik) and lover of the Ferengi Grand Nagus Zek (Wallace Shawn).

"Star Trek: Deep Space Nine" showrunner Ira Steven Behr is a fan of the musician-actor and lobbied for him to be on the show. According to StarTrek.com, Iggy Pop was initially intended to appear in the Season 3 episode "Past Tense, Part II," but the sinewy, gravelly-voiced punk veteran had to pull out due to scheduling conflicts. It's all for the best, however, as Yelgrun got to share the screen with one of the "Star Trek" ensemble's most dependable players, Jeffrey Combs. Iggy Pop was a longtime friend of glam icon David Bowie, who was married to the previously-mentioned Iman.

Tom Morello

Rage Against the Machine and Audioslave guitarist Tom Morello has shown up in "Trek" twice. The singular musician first had a cameo as an uncredited S'ona in "Star Trek: Insurrection," and later in the Season 6 episode of "Star Trek: Voyager" "Good Shepherd" as Starfleet science officer Mitchell.

Speaking with Loudwire in 2019, Morello professed his love of all things "Star Trek." "It began with Gene Roddenberry's vision. The smarts, the humanity, and the sci-fi geekiness are three things that I love a lot. I didn't grow up on 'Star Trek,' I discovered it while unemployed, living in Hollywood in the mid-'80s." The rocker added, "Captain Janeway was very gentle with me and sort of helped me through the scene. It convinced me that, on the one hand, I may not want to quit my day job as a guitar player, but I feel honored to be a part of the 'Star Trek' pantheon." On the special edition DVD of "Star Trek: Insurrection" there is a hidden bonus feature with an on-set interview with Morello.

Kirsten Dunst

Actress Kirsten Dunst, who was recently nominated for an Academy Award for her supporting role in "The Power of the Dog," became part of "Star Trek" history early in her career at the tender age of 11. Dunst's brush with the Federation came in the form of a "Star Trek: The Next Generation" Season 7 episode titled "Dark page" by Hillary J. Bader, who also wrote numerous episodes of DC animated series like "Superman," "Batman," and "Batman Beyond."

A member of the telepathic Cairn race, Dunst's character is named Hedril. The Cairn is a species with no natural gift for spoken language. Hedril is the tutee of Lwaxana Troi (Majel Barrett) and has transcended the Cairn's verbal limitations. Dunst's "Trek" performance preceded her star-making turns in1994's "Interview With a Vampire," "Little Women," and 1995's "Jumanji." In 2016, Dunst paid tribute to her time on "Star Trek: The Next Generation" with a behind-the-scenes post on Instagram.

Tom Hardy

2002's "Star Trek: Nemesis" may be one of the more maligned films of the TNG era, but it does have some things going for it. "Nemesis" deepened the mythology of the Romulan race by delving into their internal politics and introducing their vampiric sister species, the Remans. It also features an absolutely bonkers performance by a young Tom Hardy (fresh off of bit parts in "Band of Brothers" and "Black Hawk Down") as Praetor Shinzon, an outcast clone of Jean-Luc Picard who seizes power on Romulus and wages war against his genetic ancestor.

Lithe, disguised by a fake nose and garbed in a luminescent cloak, the Hardy of "Star Trek: Nemesis" hardly resembles the burly character actor we've come to know in recent years. But even back then, he was going for broke with his acting. The thing is, he may have been pulling his punches. In his screentest footage opposite Patrick Stewart (available on the home video release of "Star Trek: Nemesis"), you can get a taste of how his Shinzon could have been even more magnetic on the big screen. 

Christian Slater

One of the most jarring cameos in all of "Trek" has to be Christian Slater's appearance in a few frames of "Star Trek: VI: The Undiscovered Country." Slater plays a Starfleet night shift officer aboard the USS Excelsior who wakes commanding officer Capt. Sulu with urgent news.

Having served as the casting director for films like "9 ½ Weeks" and "Street Fighter," Slater's mother, Mary Jo Slater, has an extensive history in Hollywood. When she got the assignment for "Star Trek VI: The Undiscovered Country," she did her son — a big-time Trekker — a solid and cast him in a small role, even though his career as a teen heartthrob was already exploding. In 2017  Christian Slater told Jimmy Kimmell that his uniform from the film was originally worn by William Shatner in "Star Trek II: The Wrath of Kahn," and that he surreptitiously kept it as a memento after completing his day of shooting.

John Tesh

John Tesh wears many hats. For years, he co-anchored "Entertainment Tonight." He recorded the hooky theme song to "The NBA on NBC," has authored self-help books, and hosts a podcast. In 1989, he donned the wig and greasepaint as a (holographic) Klingon warrior in the "Star Trek: The Next Generation" episode "The Icarus Factor." As someone who grew up watching the original series, Tesh called his experience on the TNG set "a dream come true," as he revealed in an early '90s "Entertainment Tonight" segment.

In an interview with the New Hampshire Union Leader, Tesh explained how he got the part. "I was at the Paramount Studios gym, and I saw one of the producers of 'Star Trek: The Next Generation.' I said, 'Hey, just so you know, if you ever need anybody to play the captain's assistant or something like that, I'd be glad to.' About six months later I get this call from the "Entertainment Tonight" assignment editor saying, 'Hey, the guys at 'Star Trek' want you to come be on the show.'" Tesh even got his own official "Star Trek" trading card.

Jane Wiedlin

Another famous rocker had a role on "Star Trek" — Jane Wiedlin of The Go-Go's. Wiedlin's nerd credentials are certifiable, having also appeared in "Clue" and as Joan of Arc in "Bill & Ted's Excellent Adventure." Wieldin's scant seconds of "Star Trek" fame came in the form of a walk-on in "Star Trek IV: The Voyage Home" as communications officer Trillya aboard the USS Shepard. The alien race to which she belongs has not been specified in canon.

"'Star Trek' was the highlight of the week for my family when I was growing up," Wieldin told StarTrek.com in a 2011 interview. "[Me and my siblings] watched every episode when they were originally aired, and then we would recreate the episodes. We even made our own 'Star Trek' movies with Super 8 cameras ... I've been a geek girl since the '60s." Like many dyed-in-the-wool Trekkers, Wiedlin begged for a part in the film and said it was one of the highlights of her career to take direction from Mr. Spock himself, Leonard Nimoy.

Sarah Silverman

Comedienne Sarah Silverman earned her "Trek" bona fides in an episode of "Star Trek: Voyager." Silverman had a role in two third season episodes, "Future's End" and "Future's End Part II." She played Rain Robinson, a late 20th-century SETI scientist in search of extraterrestrial life. In a nod to the film "Star Trek IV: The Voyage Home," these episodes are yet another "Trek" time-travel story (the Vulcan officer Tuvok even dons a durag to conceal his pointed ears, not unlike what Mr. Spock did with a headband in that 1986 movie).

In 2011, "Star Trek: Discovery" creator (and previous contributor to "Star Trek: Deep Space Nine" and "Star Trek: Voyager") Bryan Fuller revealed that at one time, there were plans to make Silverman's character a series regular on "Voyager." Fuller elaborated to Trekmovie.com, "It was ['Star Trek: Voyager' executive producer Brannon Braga's] desire to bring Rain on board because he enjoyed writing for Sarah and the freshness she brought to the show."

Ashley Judd

One of the more prominent "Star Trek: The Next Generations" cameos came courtesy of a 23-year-old Ashley Judd in her first official on-screen credit. Judd's Ensign Robin Lefler appeared twice on "Star Trek: The Next Generation," first in the seminal episode "Darmok," and again in the Season 5 episode "The Game," in which it was revealed her character had a romance with Wesley Crusher. The former is notable for being one of TNG's high-water marks, the latter for being one of its silliest entries.

In speaking with Anderson Cooper in 2012, Judd recalled how she got the part. "Actually, I auditioned for something else that day, and they started whispering about me which is usually a good sign that you're gonna, like, go in and see the producers and the head of the studio or something, and they said, 'Um, we know you didn't come in for this, but may we cast you in 'Star Trek' right now? And could you go directly to wardrobe because there are no bras in space?'"

Dwayne Johnson

Do you smell what The Rock is trekking? Very early in his acting career, famed WWE wrestler Dwayne "The Rock" Johnson played an unnamed Pendari fighting champion in the "Star Trek: Voyager" sixth season episode "Tsunkatse." The episode's plot concerns the kidnapping of Jeri Ryan's transhuman Borg survivor Seven of Nine, who is forced to engage in combat at the hands of Norcadians.

Johnson's only two non-wrestling appearances up until this point had been on the television series "That '70's Show" (which also featureS "Star Trek" alum Kurtwood Smith) and "The Net." Johnson is far from the only professional wrestler to wade into the 'Trek' waters. Tom Magee appears in the "Star Trek: The Next Generation" episode "Devil's Due," Tommy "Tiny" Lister features in the premiere of "Star Trek: Enterprise," and Paul White (Big Show) also appears in an episode of "Enterprise." Of her time working with The Rock, Ryan told Big Issue, "The first time I met him was a fight rehearsal, and he came in and he was just a super sweet, unassuming gentle guy named Dwayne."

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