When an executive for a global pharmaceutical company is found dead in Montreal, his wife Sarah's world is thrown into a tailspin. With the ensuing investigation led by garda Emer Byrne revealing more questions than answers, Sarah suddenly finds herself under suspicion, and her life under surveillance.

DSI Stella Gibson continues her game of cat and mouse with serial killer Paul Spector in the third series of this smart psychological thriller. She has arrested Spector, but will he survive the gunshot wounds? Will he ever face justice?