A suicidal man kills several people when he causes a catastrophic train crash, and Sam struggles to cope after one of the young victims dies in his arms.

When a person is found dead in the cells, Sam becomes the main suspect, leaving Ronnie and Wes facing a race against time for them to get their hands on the real culprit.

A man is found dead in a hotel room owing his ex-wife thousands of pounds in child support. The child's grandfather is the only suspect, but is the case that easily solved?

When the body of a woman is pulled from the Thames after her car is found in suspicious circumstances, the victim's abusive ex-husband seems to be the prime suspect.

A gay father is found beaten to death and the son that he adopted with his partner is missing. In a race against time, Ronnie and Sam go on the hunt for the missing boy.