As Roy and the team deal with recent distressing events, they are called to the scene of a car accident in which a local hotelier was killed by a driver who fled the scene and left him to die. As Grace tackles what may prove to be one of his most complex cases yet, DC Vee Wilde faces a challenge of her own when she comes face-to-face with her estranged father after many years. Meanwhile, Grace's life takes a devastating turn as his wedding to Cleo draws near.

Roy and Bella investigate a murder on a council estate after a teenager is stabbed to death , with signs initially pointing to it being drug-related, but the victim's parents are adamant that their son had nothing to do with drugs. The investigation brings Grace face to face with someone from his past and stirs up old demons that worry Bella, with the case placing one of the team in grave danger. Meanwhile, Branson's investigation into a masked armed robbery leads to tensions in CID.

As Roy and Branson take steps to verify Cassian's intel about Sandy's murder, the body of student Charlie Downing is found in a sea lock, and Grace must find out who wanted this young woman dead. As the team investigates the campus, it becomes clear that the university harbours secrets that could be connected to Charlie's death. Grace soon has his sights set on a killer who will stop at nothing to prevent one particular truth from getting out.

The aftermath of ACC Cassian Pewe's betrayal hangs heavily over East Sussex Police several months on as the team is in the midst of an anti-corruption enquiry while Roy wrestles with whether to trust Cassian's intel about Sandy's murder and the threat to Bruno's life. Meanwhile, his team is plunged into a case filled with secrets after a Brighton property developer reports his wife missing.