The Center Seat: 55 Years of Star Trek

There's not much here that a well-informed Trek fan doesn't already know, but it's still nice to have it all collected in one place. The documentary is unusually candid about some of Trek's scandals and behind-the-scenes conflicts, and doesn't waste time recapitulating the plots of episodes and movies. There's a good choice of interviews, which include not just main cast members but also writers, producers, production designers, and guest stars.