DeForest Kelley may have made his name in Hollywood playing villains and cowboys, but his legacy will forever be led by Doctor McCoy, the cantankerous yet empathetic doctor aboard the USS Enterprise, playing an emotional foil to the logical Spock. It seems fitting, then, that his last acting role was that of the first successful Mars lander, Viking 1.

The Brave Little Toaster Goes to Mars, released in 1998, was the third and final film in the Brave Little Toaster series, started by The Brave Little Toaster in 1987. The franchise follows five household appliances — a toaster, an electric blanket, a radio, a vacuum, and a desk lamp — and their various adventures, unbeknownst to their owner.

In Mars, the owner's infant son is accidentally abducted to Mars after a mix-up involving a hearing aid created by Albert Einstein (just go with it.) With the help of a microwave and ceiling fan, they rig up an impromptu ship, and travel to space to retrieve the baby before their owner wakes up.

Once they crash on the surface of the red planet, they're greeted by an imposing spacecraft — Viking 1. "The satellite?" asks the vacuum, and in a familiar voice, the craft fires back "No, Viking 1 the bagel. Of course the satellite!"

Viking 1, of course, is voiced by DeForest Kelley, in his only non-Trek voice acting role. "It was one of the first roles I've ever played where I had no idea what to do," Kelley said in an interview with The New York Times. "How do you give voice to a satellite?"

His hesitation on how to voice a spacecraft didn't cloud his excitement for the project. "They had quite a cast for it, I thought, with Carol Channing, Farrah Fawcett and Alan King. I didn't meet any of them because, like we did with the old animated Star Trek show, everyone recorded their dialogue separately."

"I'm glad I did it," Kelley said. "I hear it came out very nicely, and I hope people will be entertained by it."

Kelley, unfortunately, passed away in 1999, a little over a year after The Brave Little Toaster Goes to Mars was released. He was not the only actor to have their final work on the movie — Thurl Ravenscroft, who voiced Kirby the vacuum in the movie but who you probably know as the voice of Tony the Tiger and the singer of "You're a Mean One, Mr. Grinch" also gave his final performance in this movie. It was also the final non-documentary role of Carol Channing, who voiced Fanny the ceiling fan.