Newly appointed DI Wes Leyton faces a tough challenge when looks like a colleague has taken the law into his own hands. After being convicted of manslaughter for driving onto a railway killing 15 people, Finn Tyler was found hanged in a court holding cell – and DS Sam Casey was seen walking away.

Sam was left shaken by the tragedy and, when he can’t explain why he was outside Tyler’s cell, he’s suspended while Wes gets involved in the case, with a reluctant DS Ronnie Brooks as his partner.

Meanwhile, after a few drinks, Jake opens up to new colleague Kate Barker about his mothers’ death. Also, Ronnie’s estranged daughter turns up and Sam spends the day with his son.