The success of recent shows like Strange New Worlds has proven that Star Trek still has staying power even today. With a show as groundbreaking as Trek, the cast was destined to become stars because of their time exploring the final frontier. Even so, many of The Original Series cast members had successful careers before they were even on Trek.
From veteran TV actors like DeForest Kelley, to bonafide screen stars like Leonard Nimoy, the cast of TOS made a name for themselves outside of the confines of the Star Trek franchise. Though they mostly had successful careers, some projects starring the TOS cast gained much higher scores on IMDb.
Majel Barret - Westworld (1973) 6.9
Most known as Nurse Chapel on TOS, and Lwaxana Troi on The Next Generation, Majel Barrett was also an integral figure behind the scenes in the Trek franchise. In Westworld, Barrett returned to her Sci-Fi roots in a film about a futuristic amusement part that immerses guests into different themed lands. When a malfunction occurs, a gunslinging android wreaks havoc on the unsuspecting visitors.
Barrett stars as Miss Carrie, a brothel madam that appears in the Western portion of the park. Stepping back to her days as a frequent guest star on Western TV shows, Barrett is able to flash a bit of the sly humor that she was known for in Star Trek. While the film is a largely forgettable piece of '70s cheese, it did inspire a more serious TV reboot.
Grace Lee Whitney - Some Like It Hot (1959) 8.2
While she only appeared in a handful of early episodes, Grace Lee Whitney nevertheless shined as the spunky Yeoman Rand. Before her time in the 23rd century though, she got a chance to play a small role in one of Billy Wilder's best films. Some Like It Hot is the story of two musicians who witness a brutal mob hit. To escape Chicago, the pair disguise themselves as women and join an all-female band on their way to Florida.
Whitney had fun with her walk-on role, and was one of the many musicians in the band. Even though she didn't get a chance to do too much in the film, Whitney's appearance alongside Marilyn Monroe was an accomplishment that few other Trek actors could boast. Some Like It Hot may be somewhat problematic by today's standards, but the brilliant performances helped to elevate it beyond the typical 1950s comedy fare.
Walter Koenig - Babylon 5 (1993-1998) 8.4
Jumping from one Sci-Fi series to the next, it seemed as if Walter Koenig was destined to stay in space forever. Babylon 5 is set on the titular space station that acts as a friendly port for all of the disparate alien races of the galaxy. In the middle is the Earth commander whose job it is to keep the peace despite constantly rising tension between alien factions.
The former Ensign Chekhov appeared in several episodes of the ongoing series as Alfred Bester, a Psi corp operative who was tasked with policing psychics throughout the galaxy. Shaking typecasting, Koenig's sinister turn as Bester was unlike anything fans had seen from him before. Taking a darker tack than Star Trek, Babylon 5 was much less optimistic about the future.
DeForest Kelley - Have Gun - Will Travel (1957-1963) 8.4
Perhaps the most accomplished actor coming into his time on Star Trek, DeForest Kelley was a veteran of the small screen. Guest starring in many of the best Western TV shows of all time, Kelley's best turn was in Have Gun - Will Travel. The show followed Paladin, a gunfighter for hire who roamed across the West making money and settling scores.
In the episode "The Treasure", Kelley appears as Deakin, a greedy man who hopes to make a fortune by killing a man believed to be a thief. While he was crotchety as Dr. McCoy, his role on Have Gun - Will Travel was a unique look for longtime Trekkies. In its time, the show had to compete with a score of other Western programs, but it set itself apart by maintaining a loose set of morals and a main character who existed outside of the boundaries of the law.
Nichelle Nichols - Batman: The Animated Series (1992-1995) 9.0
After shattering boundaries on TV with her role as Uhura on Star Trek, Nichelle Nichols settled into smaller parts, mostly relying on her silky voice. Batman: The Animated Series brought many of Batman's best storylines to life in a fun and exciting weekly animated TV series.
Appearing in one episode as Thoth Khepera, an ancient Egyptian queen resurrected by Ra's al Ghul, Nichols flexed her vocal acting chops. The series featured a wealth of famous actors, and even pulled many Star Trek alumni as well. The series shined because it managed to present Batman in an easily digestible format, that was fun for younger and older viewers simultaneously.
James Doohan - The Twilight Zone (1959-1964) 9.1
The Twilight Zone was must-watch TV for its entire run, and it called in many future stars to inhabit its creepy weekly stories. James Doohan's career would be defined by his time as Scotty, but he had made several TV appearances before he donned a Starfleet uniform. The episode "Valley of Shadows" tells the story of a reporter who finds himself trapped in a town filled with technological miracles.
Doohan appears as the character simply known as Father, and gives a subtly creepy performance to match the overall mood of the episode. Though it isn't one of the most well-remembered episodes of the series, it is nevertheless one of the scariest tales ever presented on the show.
Leonard Nimoy - The Twilight Zone (1959-1964) 9.1
Moralistically speaking, Star Trek and The Twilight Zone both used allegory to present their view of right and wrong. Leonard Nimoy cut his teeth in several TV series before becoming the pointed-eared Vulcan, Spock, and his time on The Twilight Zone was a career highlight. In the episode "A Quality of Mercy", a ruthless Lieutenant attempts to order his men to fire on helpless Japanese soldiers in the dying days of WWII.
Nimoy plays one of the soldiers who refuses to act, and he doesn't steal the spotlight away from the episode's star, Dean Stockwell. While the episode is extremely problematic for its makeup choices, the moral lesson of the story is just as strong today as it was back then.
William Shatner - The Twilight Zone (1959-1964) 9.1
Carrying an entire series is a difficult task, but William Shatner proved that as Captain James T. Kirk, he was up to the challenge. Before he took the captain's chair though, Shatner appeared in a plethora of movies and TV shows, but none were as memorable as his hammy turn on The Twilight Zone. "Terror at 20,000 Feet" follows a man with a debilitating fear of flying, who believes he sees a strange creature on the wing of his airplane.
A far cry from the confident Captain Kirk, Robert Wilson's nerves get the best of him almost immediately. Though unbelievably cheesy, the episode is still a great example of what the show had to offer, and it allowed Shatner to shine as a one-man tour de force.
George Takei - Avatar: The Last Airbender (2005-2008) 9.3
Beloved doesn't even begin to describe Avatar: The Last Airbender, and many believe it to be one of the best animated series of all time. George Takei worked in film and TV doing dubs of Asian programs before he landed the role of Sulu on Star Trek. Most known for his sonorous baritone voice, Takei fit right in with the cast of the show. Avatar followed the adventures of Aang, an Airbender who helps defend the land from the encroaching Fire Nation.
Takei lends his voice to the role of a prison warden, and though small, it is unmistakably him. Joining an amazingly stacked cast, Takei was the perfect choice for any role on the show, and he knocked it out of the park. Though brief, Avatar combined great writing, wonderful artwork, and brilliant performances together into a concoction of perfect TV entertainment.