It's been a quiet year for the Thursday Murder Club. Joyce is busy with table plans and first dances. Elizabeth is grieving. Ron is dealing with family troubles, and Ibrahim is still providing therapy to his favourite criminal. But when Elizabeth meets a wedding guest who fears for their life, the thrill of the chase is ignited once again. A villain wants access to an uncrackable code and will stop at nothing to get it. Plunged back into their most explosive investigation yet, can the gang solve the puzzle and a murder in time?