4x2 - Blue Murder

When construction company owner Richard Marr goes missing, the squad is brought in by his devastated wife Peggy, but the squad soon learns that Marr was a child molester who faked his own disappearance to get away from the angry parents of his victims and the criminal charges associated with it. Forensics specialist Roberta Thorpe asks Ed to prove the innocence of her young colleague Noel Watson in the death of his wife, but she ends up coming under suspicion herself.