After the sudden death of her sister, devastated detective DS Ronnie Blake relocates to Cambridge to help her brother Alex raise their sister's young son, Noah. She reports for her first day but instead finds herself being questioned by a special investigations unit, nicknamed the DEAD Team.

With a small group of six, led by DI Fenton, the once-successful DEAD team has a single outstanding case, Operation Byron, and the failure to resolve it threatens the unit's existence. Their most promising lead is an anonymous note linking three seemingly unconnected people: a convicted fraudster, a dead academic... and Ronnie's sister Jodie.

When Ronnie is denied information about Operation Byron, she follows a lead slipped to her by Malachi, the youngest member of the team, and makes a discovery which links Operation Byron to a disturbing unsolved murder. She is rapidly drawn into an intricate web of deceit, buried secrets and tragedy and the discovery that her connection to Cambridge is far darker than she could ever have guessed.