Detective Inspector Brent Hyatt and Detective Sergeant Chris Hoar, are summoned to University College Hospital in Central London to interview a patient with an extraordinary story to tell.

The day after Litvinenko's death, radiation teams swarm across London to secure potentially contaminated sites visited by the Russian spy.

A team of detectives led by Timmons' 'best man' Brian Tarpey arrive in Moscow hoping to interview Lugovoy and Kovtun, now the prime suspects behind Litvinenko's murder. Tarpey and his men are promised full cooperation from the Russian prosecutors and are swiftly taken to interview Kovtun, who they are told has also been poisoned.

With their investigation complete, Timmons' team submit their file to the Crown Prosecution Service, who charge Lugovoy and Kovtun with Litvinenko's murder. However, with the killers safe in Russia and protected by Putin, the chances for true justice appear to be slim.