There is a lot of crossover between science fiction and horror, owing to a shared fanbase and frequent blurring of the lines between them. It’s no surprise then, that many horror movie actors have crossed over into a durable sci-fi franchise and vice versa. In fact, numerous Star Trek alums have made an impact in the horror field – including starring roles in legitimate genre classics – and even those that weren’t brilliant were notable for other reasons. Here are ten of the most prominent movies, featuring actors from every stage of Star Trek’s early history.

DeForest Kelley - Night of the Lepus (1972)

The weakest films open this list, which speaks a great deal to Star Trek's status at the time. The Original Series was canceled after three seasons, and while the fan base slowly built over syndicated reruns, the cast moved on to other work. Nature-run-amok movies were big business in the early 1970s, boosted by the likes of 1971’s Willard and reaching their apex with 1975’s Jaws. Night of the Lepus was far down on that scale, largely because of its choice of animal.

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Based on a 1964 novel called The Year of the Angry Rabbit, it depicts an infestation of rabbits grown to enormous size and running rampant through a small ranching town. DeForest Kelley – who was largely known for playing cowboys before Star Trek – seemed to fit the director’s vision of a western-horror film, which did neither halves of the genre credit. The rabbits – domestic bunnies rather than wild jackrabbits – were shot in slow motion devastating miniature buildings, while close-up attacks relied on what was clearly a man in a rabbit suit for the effect. The only comfort Kelley could take was the company: horror legend Janet Leigh starred in the film too.

Willian Shatner - Kingdom of the Spiders (1977)

William Shatner climbed a little higher up the horror ladder than his Trek costar Kelley, though not much. 1977’s Kingdom of the Spiders found him as an Arizona veterinarian contending with an invasion of tarantulas. In a 1988 issue of Fangoria, producer Igo Kantor claimed to have used 5,000 live spiders during the production. While they give the film a certain creepiness, it struggles to make them sufficiently frightening, leaving the impression that the protagonists could simply squash their way to safety. Shatner didn’t help. Sporting a bad toupee and trying desperately to appear 15 years younger than his actual age, he turned the entire exercise into camp, leaving it a memorable-for-all-the-wrong-reasons wreck.

Leonard Nimoy - Invasion of the Body Snatchers (1978)

Of the Original Series’ “Big Three,” it was Leonard Nimoy who snapped the horror movie losing streak. The actor was actively trying to distance himself from Mr. Spock at the time and found the ideal part in Phillip Kaufman’s terrifying remake of the ubiquitous alien invasion story. His self-help guru is one of the earliest figures replaced by a pod person and uses his calm, reasonable demeanor to actively gaslight anyone who suspects the truth. His character's easy smile and seeming compassion run in direct contrast to Mr. Spock’s famous logic, making his ultimate betrayal of the protagonists all the more shocking. The actor returned to and eventually embraced Spock, but in the interim left a disquieting performance in one of the scariest movies ever made.

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Robert Picardo - The Howling (1981) and Matinee (1993)

Robert Picardo was a well-established actor before appearing as the Doctor on Star Trek: Voyager, most notably in his frequent collaborations with Joe Dante. The Howling put him on the map with a character as different from the Doctor as night and day. His Eddie Quist was a serial killing werewolf, sought out by Dee Wallace’s news reporter, which leads her to the film’s lycanthrope colony deep in the California redwoods. That gave him the movie’s signature transformation moment, but it’s the character’s ghoulish sense of humor that stands out, going from a one-note cliché into someone far more interesting in the actor’s capable hands. 12 years later, Picardo appeared in Matinee, Dante’s affectionate homage to gimmick horror king William Castle. Most of the movies on this list are R-rated and for adults only. Matinee makes a good choice for Trek fans looking for something gentler this Halloween.

Patrick Stewart - Lifeforce (1985)

Patrick Stewart dipped his hand into science fiction and horror well before his career-defining role on Star Trek: The Next Generation. He had appeared in 1981’s Excalibur as a loyal Arthurian knight and in David Lynch’s Dune as Gurney Halleck. But neither of them were quite as off-the-wall as Lifeforce, an effort by the infamous Cannon Pictures to break out of their typical grindhouse fare and present an A-list horror picture. Tobe Hooper of The Texas Chain Saw Massacre fame was brought in to direct, with a screenplay co-written by Alien’s Dan O’Bannon and a $25 million budget that could attract a talented actor like Stewart. The results, unfortunately, were more silly than scary, topped by a moment in which Stewart’s fussy hospital administrator – possessed by the spirit of a nude female space vampire – kisses the leading man full on the mouth.

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Jeffrey Combs - Re-Animator (1985)

Like Picardo, Jeffrey Combs was well known among horror fans before his first appearances in Star Trek and has dozens of genre films on his resume that could fit this list. It began with Stuart Gordon’s unhinged adaptation of the H.P. Lovecraft story, placing Combs’ delightfully off-his-rocker Herbert West front and center. The actor parlayed that into a long career, which included a great deal of time in the make-up chair. That later proved invaluable on Star Trek, when he played a wide variety of different characters – from the Vorta Weyoun to the Andorian Shran – requiring copious prosthetics. His work continues in the franchise with a cameo on Star Trek: Lower Decks in 2021.

Denise Crosby - Pet Sematary (1989)

Pet Sematary Denise Crosby

Denise Crosby’s departure from The Next Generation after a single season remains a talking point among fans, and her subsequent reappearance in the franchise is a sign of how much potential walked away with her. One of the films she made in the wake of it all was Pet Sematary, based on the Stephen King novel about a haunted patch of ground that brings those buried in it back from the dead. The film is deeply underrated – smarter than the unfortunate 2019 remake and with a far better grasp of the source material – aided by Crosby, whose grieving mother is unaware of how complicit her husband is in the horrors unfolding.

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Scott Bakula - Lord of Illusions (1995)

Before starring as Captain Archer on Star Trek: Enterprise, Scott Bakula was best known for his role on Quantum Leap: a part that earned him a unique fan. Clive Barker sat down to pen the screenplay for his horror movie Lord of Illusions in 1991 – in the middle of Quantum Leap’s run – and claims on the DVD commentary that Bakula was his ideal choice for the lead. The story concerns a famous stage magician whose tricks may be more than smoke and mirrors. Bakula’s “supernatural detective” Harry D’Amour seeks the answers, aided by the magician’s wife, played by fellow Trek alum Famke Janssen.

Jeri Ryan - Dracula: 2000 (2000)

The decidedly weird Dracula: 2000 attempted to update the old horror chestnut for the new millennium, and while hardly high art, it has a lot of fun with its gimmicky concept. Trek alum Christopher Plummer has a great time slumming as a seemingly immortal Abraham Van Helsing, but it was Jeri Ryan who drew fans to the project. The actor plays a vain newscaster who becomes one of the Count’s three brides. More importantly, it was utterly different from her cold, detached Seven of Nine, whom she was playing on Voyager at the time. The role gave her a chance to go in a sharply different direction, as well as having some Halloween fun as a bloodsucker in white.

Nana Visitor - Friday the 13th (2009)

The Friday the 13th franchise succeeded almost in spite of itself, finding its way to its iconic monster through three or four entries in the franchise. The killer in the first film was Jason Voorhees’s mother, for instance, leaving the second film to cement the franchise boogeyman. Jason himself didn’t don his hockey mask until the third film, leaving a frustratingly slow burn for modern fans interested in cutting to the chase. The 2009 remake benefits by assembling all of the key components in the franchise’s mythology into a single movie, making it a good “all in one” option for anyone but hard-core Friday the 13th fans. It also gives Trek lovers a little Easter egg: an appearance from Star Trek: Deep Space Nine's Nana Visitor as Mrs. Voorhees, uncorking the madness and having a ball in the process.

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