Factual error: Series 8, Episode 2. A family liaison officer would not be alone on the first job.

Deliberate "mistake": In Series 1 episode 1 Nick can use a laptop fluently, yet in series 1 episode 2, Nick has to ask where the "." button is.

Continuity: When Nick becomes a taxi driver, he gives Ben a lift to the cinema. But he sets off in an exorcist's outfit and arives in plain clothes. If he was driving, he couldn't have got changed.

Continuity: Throughout the first series Ben and Susan's bedroom had the window on the left of the screen and the bathroom on the right. In the second series onwards the bathroom and the window have mysteriously swapped around. Also the entire layout of the house changes dramaticly.