The Odd Job (1978)

Arthur Harris (Graham Chapman) is a happily married man who returns from his job to discover that his wife, Fiona (Diana Quick), is leaving him. Devastated he gets really drunk and tries to commit suicide. After a few setbacks and while he is trying to electrocute himself with a lamp, the door bell rings. An odd man in a leather coat asks if there are any odd jobs that he can perform. Arthur hires the man (David Jason) to kill him. The next day his wife returns, but the man he hired is still trying to kill him...