Donald P. Bellisario's beloved NBC series strands physicist Sam Beckett (Scott Bakula) inside other people's bodies throughout history after a time-travel experiment goes wrong, leaving him to correct some injustice in each new life before he can leap again — always hoping the next jump sends him home. Al (Dean Stockwell), a wisecracking hologram only Sam can perceive, serves as his guide, sounding board, and comic relief across nearly a hundred episodes ranging from civil rights drama to pure screwball comedy. The show's anthology structure let it tackle era-specific social issues with a sincerity rare for genre television of its time. Its unresolved, bittersweet finale remains one of the most debated endings in TV history.