Ordinary man-in-the-street Arthur Ferguson Jones leads a very straightforward life. He's never late for work and nothing interesting ever happens to him. One day everything changes: he oversleeps and is fired as an example, he's then mistaken for evil criminal killer Mannion and is arrested. The resemblance is so striking that the police give him a special pass to avoid a similar mistake. The real Mannion sees the opportunity to steal the pass and move around freely and chaos results.