A suicidal man drives his car across a railway causing a massive train crash and killing over a dozen innocent passengers, but somehow he survives. Crown Prosecutor Jake Thorne pursues the culprit with vigour whilst the man's defence barrister tries to prove his vulnerability and mental illness. Just as the case finishes, CPS Director Henry Sharpe springs one more surprise on Jake… Alesha's replacement. Another new face is DI Wes Leyton, an old colleague of Ronnie's, who is covering for DI Chandler when a suspect is found dead in his cell at court, and the last person seen entering the cell was DS Sam Casey.

A man is found shot dead in a hotel room and the cash he was carrying has gone missing. Sam and Ronnie learn that the man owed his ex-­wife thousands of pounds in unpaid child support, was lying to his girlfriend about his line of work, and has a son dying of leukaemia, but hadn't been tested for a bone marrow match. Attention turns to the ex-­father-­in-­law, did he hunt down the father of his dying grandson to try to recoup the unpaid money or is there more to this family set up than first appears? At the CPS Jake and Kate try to work through their differences and reach a more even keel.