The team discover that Paul may not be who he actually says he is and they then discover he has been involved in a murder case before now. A revisit to the victims of Paul's first murder victim's family reopens old wounds, as more and more victims come to light. The last link in the chain may be in Sasha's hands, but is she too close to her clients to help solve the case.

The body of an armed police officer is found as the investigation continues. The team join the manhunt for a supposed cop killer named Bruno. Jack hopes to reach the killer first and believes he can talk him into handing himself in, before more murders are committed. As he continues his own investigation, he soon uncovers links to the gun trade in London. The other armed police officers are questioning their safety after the murder and it soon becomes apparent that the killer is very highly trained, putting more pressure on Jack and the links he has uncovered.