Trevor Reznik has not slept for a year. His shockingly deteriorated physical and mental health has made his every waking moment an unrelenting state of confusion, paranoia, guilt, anxiety and terror. The only solace from his living nightmare is from an affectionate prostitute. When cryptic notes turn up mysteriously in his apartment and when hallucinations of a co-worker no one else sees causes a gruesome machine shop injury, he embarks on a journey to discover whether there is an elaborate plot to drive him insane or if his fatigue has simply robbed him of reason.