Donnie is a troubled high school student: in therapy, prone to sleepwalking and in possession of an imaginary friend -- a six-foot rabbit named Frank, who tells him the world is going to end in 28 days 06 hours 42 minutes and 12 seconds. During that time he will navigate teenage life, narrowling avoid death in the form of a falling jet engine, follow Frank's maladjusted instructions and try to maintain the space-time continuum.