Small-time solicitor Harry Venn is forced to revisit his murky past when he is approached by a mysterious and glamorous lawyer, Gina Hawkes, looking for a missing alibi witness for her client. Harry quickly finds himself plunged into a deep and dangerous conspiracy.

With his office blown to pieces, Harry is determined to find out who Gina Hawkes is. He gets his friend and accomplice, Frank Hanna, to break into her doctor's office to access her files. But when Hanna is chaseфd out by armed heavies he realises they are caught up in something far more dangerous than they originally thought.

In Paris, Harry and Gina are held at gunpoint by Hillman - only to find themselves saved by a masked gunman. Tanzir has been mortally wounded, but Harry hears him say "Styles" with his final breath. Harry confronts Gina about why she's been lying up until now and discovers that her parents died 20 years ago, on the same night Mark was murdered.

In the aftermath of the shootout in Kent, Frank Hanna lies injured. Unable to alert the police to what's happened, Harry and Gina drop him at a hospital and head to see Joe Collins in a hotel room near Heathrow. Collins is in a desperate state. He tells them he was hired to do a job for Styles a while back but changed his mind. However, rather than walk away, he made the fatal mistake of stealing his laptop. Realising its contents probably hold the answers, Harry takes the laptop and heads to Lauren's with Gina. In the morning, the two of them split up: Gina goes to Nigel Fountain for answers, while Harry finds someone to break into the laptop. Both trips deliver some unexpected truths, and Harry suddenly realises he has less than an hour to stop an event that could change everything – not just for himself but for the country. In a climactic showdown, he is forced to confront the past that has long haunted him.