Halloween H20: Twenty Years Later is a 1998 American slasher film directed by Steve Miner, and starring Jamie Lee Curtis, LL Cool J, Adam Arkin, Michelle Williams, Janet Leigh, and Josh Hartnett, in his film debut. It is the seventh installment in the Halloween franchise. H20 is a direct sequel to Halloween (1978) and Halloween II (1981), ignoring the Jamie Lloyd story arc of the previous three installments. It follows a post-traumatic Laurie Strode, who has faked her death in order to go into hiding from her murderous brother, Michael Myers, who finds her working at a private boarding school in California.

Halloween H20 was released in the United States on August 5, 1998. The film received mixed reviews from critics, with many saying it was at that point the best of the sequels but still paled compared to the original. It grossed $75 million worldwide against a budget of $17 million, making it the highest-grossing film in the franchise. A sequel, Halloween: Resurrection, was released in 2002, while a remake of the original film was released in 2007, and later another trilogy of films that follow only the original film and disregard all previous entries, were released beginning in 2018.