Eight months after her unhinged son Daniel tried to kill her DI Elaine Renko joins DI Charlie Hicks, replacing his late partner Alex Butler, as they investigate the suspicious death of computer hacker Lloyd Hammond,. She is aware of the married Charlie's affair with Alex's widow Mari. Together they link Lloyd to fellow hacker Sunny Ramachandran, who tells them that Lloyd discovered something incredible, before he too is killed. The detectives are pursued by an assassin they believe is hired by MI5 before a perusal of Sunny's phone shocks and divides them.
—don @ minifie-1