When Worlds Collide (1951)

The original disaster blockbuster: a runaway star heads for Earth, and a team races to build a space ark that can carry a chosen few off the planet. George Pal produced it in Technicolor from the 1933 novel by Edwin Balmer and Philip Wylie, with Chesley Bonestell advising on the ark's design, and its effects earned an honorary Oscar. The acting is stiff and the people-choosing drama creaks, so treat it as enjoyable spectacle rather than a serious classic. It is where later end-of-the-world movies got their playbook.