I have heard about Donnie Darko many, many times from different sources. It appears on many lists as one of the best movies you must see and it already has the cult movie status.
It stars Jake Gyllenhaal, Maggie Gyllenhaal, Drew Barrymore, Mary McDonnell, Patrick Swayze, Noah Wyle, Jena Malone and more. It tells a story of a disturbed teenager, who has a strange vistion one night. He sees a rabit who introduces himself as Frank (reference to "Alice in Wanderland) and who informes Donnie that the world will end in 28 days. From then on Donnie sees and experiences many strange things, which lead to the discovery of the meaning of Frank's words.
The movie has a misterious and dark climate. It sucks you into the action almost immediately, and it makes you watch it till the least second just to see wether Donnie's visions were true or if they were just a product of his sick imagination. The ending is quite touching as well.