Lontoon huippuetsivät ratkovat kaupungin monimutkaisimpia murhia. Samaan aikaan tiimin johtaja David Bradford etsii epätoivoisesti totuutta vaimonsa katoamisen takaa.
A series of murders point to a killer within the police force, and the case quickly gets personal.
The detectives learn of a dead schoolboy's connection to the recent suicide of a young girl.
Billie's investigation turns personal, forcing her to wrestle with personal and professional ethics.
A widow and her brother-in-law accuse each other of murder; David pleads with Mulgrew.
The team suspects the killer cop harbors racial motivations; David and Vivienne cross a huge line.