On the heels of the gripping Star Trek II: The Wrath of Kahn, which rebounded a series that had gotten off on the wrong foot, it was a return to murky territory in Star Trek III: The Search for Spock, the first Trek film directed by Leonard Nimoy. This decidedly dark outing leaves the crew of the Enterprise on the planet that was born at the end of the previous chapter, brought to life by a device called Genesis, which might also revive Spock, who was killed while triggering the device. But for a film that's supposed to be about rebirth, it's literally quite dark -- not only are most scenes shot at night, but the planet oozes magma, and in all other ways resembles an entity in the most unbecoming stages of puberty. Plus there are a bunch of odd scenes of a young Spock undergoing the trauma of a rapid regrowth from child to adult. The Klingons make their first appearance in the movie series (apart from a brief cameo of a Klingon ship in Star Trek: The Motion Picture), and everything they are involved with is particularly nasty, making for a movie that's often unpleasant and brooding. It doesn't exactly derail the series, but many a viewer probably breathed a sigh of relief when Star Trek IV: The Voyage Home came along and injected a much-needed sense of humor into the saga.