To catch a killer couple...

SMIRKING and laughing, sadistic serial killer Fred West is being interviewed about his missing teenage daughter as police dig up his patio.

- BY SARA WALLIS

As we see footage of paving slabs being levered up from the garden of 25 Cromwell Street in Gloucester, in February 1994, we hear the creepy tape as West talks to detectives. This documentary is gripping from the off as three episodes rake over the lives and crimes of Britain's most notorious and prolific husband and wife serial killers.