A sudden tragedy pulls Becky into Chloe's world in a way she never imagined.

After a cyberattack exposes every undercover agent in Britain, a certain tech-challenged former agent emerges from retirement to catch the hacker.

Quan is a humble London businessman whose long-buried past erupts in a revenge-fueled vendetta when the only person left for him to love – his teenage daughter – dies in a senseless act of politically-motivated terrorism. His relentless search to find the terrorists leads to a cat-and-mouse conflict with a British government official whose own past may hold the clues to the identities of the elusive killers.