Star Trek: The Motion Picture (1979)

The most like serious science fiction, and the slowest. Robert Wise, an Oscar winner brought in to give the first film weight, made it as a stately space epic: a vast, unknown force destroys three Klingon cruisers and heads for Earth, and Kirk returns to a newly refitted Enterprise to meet it. Jerry Goldsmith's score is one of the best things the franchise ever produced. Its long effects sequences test patience, but if you love the cerebral, slow-burning side of science fiction, it has the most thoughtful premise in the series. Set five years after the original show, it reintroduces the crew from scratch.