Matt finds a seriously battered man, the former mayor of St Davids, in the boot of a stolen car after a high speed chase. Mt Thomas CI investigates, but with Jonesy away at detective's training school, Amy finds good help hard to find. She strongly disapproves of Matt's aggressive approach to questioning witnesses, but who can she turn to? Kelly is too messy, Susie too nice, and Joss - well - Amy uncovers the true motive for the assault when she learns about the victim's long and secret history of family violence while Matt, abandoned at the hospital, does some investigation of his own. When the truth is finally revealed Matt and Amy realise they have both come to the same conclusion. Meanwhile, Joss decides to prove he's worthy of Amy's respect. He relentlessly pursues a minor burglary, suspecting it as a front for a major crime.