Famous People You Didn't Know Were On 'Star Trek: The Next Generation'

List Rules
Vote up the most surprising celebrity guest stars to cross paths with the Enterprise.

For the uninitiated, Star Trek: The Next Generation might just seem like a dated sci-fi show from the late '80s and early '90s. But true fans know the series was easily one of the Star Trek franchise's best, and rewatching the series to catch some surprise guest stars makes watching the sci-fi staple - which was often directed by its actors - even more fun. Star Trek cameos run the gamut from then-unknown actors like Teri Hatcher to seasoned stage and TV veterans like Kelsey Grammer.