Jaws

The best film in this category, and the reason it works is that almost everything went wrong.

The mechanical shark did not function in salt water. Spielberg lost so many shooting days that the schedule went from 55 to 159, and he shot around the thing he could not use: a yellow barrel, a point of view gliding under a raft, John Williams doing two notes. The restraint the production forced on him is the entire effect, and every imitator learned the wrong lesson and showed the monster constantly.

It is also two films stapled together and the second is better. Once Quint, Brody and Hooper are on the Orca it becomes a three-hander about class and competence, and the Indianapolis speech is the best-written thing in the film.

It invented the summer blockbuster, the wide release and the national television campaign, which changed how every film has been sold since.

Nobody has ever regretted watching it.