Talking About 'Star Trek': In Star Trek: The Animated Series, why was Chekov replaced by an officer with three arms as the ship's navigator?

© 1973 Filmation and Paramount Television. STAR TREK © CBS Studios
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In Star Trek: The Animated Series, why was Chekov replaced by an officer with three arms as the ship's navigator?

In 1973, when Filmation got the contract from NBC and Paramount Television (the entity that inherited the Star Trek intellectual property after Paramount Pictures purchased Desilu in 1967) to produce Star Trek: The Animated Series, it faced one of the main issues that dogged creator/producer Gene Roddenberry when he was making the live action show: budget limitations.

Television networks are nothing but penurious when it comes to paying for production costs under most circumstances. They are, after all, a business entity and not a charity ward for actors, writers, producers, and directors, and they’re only willing to shell out top dollar for proven genres and well-known talent because, in the suits’ estimation, that’s what gets the audience to park its collective behind in front of the television to watch prime time shows.

During the three-year run of Star Trek: The Original Series, NBC considered the show to be the stepchild of its prime time lineup. The executives at 30 Rockefeller Plaza believed that science fiction was only one step up from children’s programming, and although NBC was willing to take advantage of public interest in space exploration - NASA’s Gemini program was winding down and Apollo (the flight to the Moon project) was gearing up when the live-action TOS premiered on Sept. 8, 1966 - it was not willing to pay top dollar to Desilu/Paramount for Star Trek.

So when NBC decided to revive Star Trek as an animated series for its Saturday morning “kidvid” lineup during the 1973-1974 season, the network asked that the show be made for as little money as possible.

As a result, Roddenberry and Paramount Television had to team up with Norm Prescott and Lou Scheimer’s Filmation, an animation company that was known for its ability to produce Saturday morning cartoons quickly and inexpensively because its artists used a technique known as “limited animation.”

Now, because NBC was not offering Filmation top dollar for Star Trek: The Animated Series, Prescott and Scheimer were only willing to hire William Shatner, Leonard Nimoy, DeForest Kelley, James Doohan, and Majel Barrett to provide voices for the USS Enterprise’s command crew. They figured that Filmation could save money by having Doohan (who was known in Canada as “The Man of a Thousand Voices”) and Barrett provide the voices for Lt. Sulu, Ensign Chekov, and Lt. Uhura.

This, of course, left actors George Takei, Walter Koenig, and Nichelle Nichols off the cast of The Animated Series, much to the displeasure of Leonard Nimoy and Bill Shatner. In an outstanding display of solidarity, they told Prescott and Scheimer that they would not sign on to reprise their iconic roles if the other actors were not included in the cast list.

Filmation, caught between a rock and a hard place, agreed to hire Nichols and Takei but pointed to the limited budget NBC had given the company and said they couldn’t sign Walter Koenig. The money simply wasn’t there.

To compensate for the loss of Chekov, the show’s producers created Lt. Arex, a three-armed Edosian, to serve as the Enterprise’s new navigator. He was one of the first non-humanoid Starfleet officers ever depicted on screen, and as Filmation had wanted, he was voiced by James Doohan.

As for Koenig? Well, obviously he was disappointed that he couldn’t play Chekov, but he still wanted to contribute to the series in some way. He eventually did so by penning the episode The Infinite Vulcan.