Hedda Jäger lost her brother Edward and Uncle Ähern in an explosive raid on their criminal lair in Italy carried out by a team of agents led by Kat Fernando four years before. Thanks to Siggi Kraft, a master of espionage and a former security analyst working for the crime syndicate TALEN operated by her uncle, she learns of Anita Franco's role leading to their deaths, but not the truth about who she really was, an undercover Agent sent by American military counterintelligence to end her uncle's reign of terror.
Impersonating Anita Franco, Hedda goes on a murderous rampage to incriminate the assassin, unaware that the woman she really wants to destroy is Kat Fernando. Other than General Wolfson and certain M-CI agents, few people know that Kat used that name to work undercover. Fearing that if she is caught she will reveal damaging information about him, Wolfson sends a hit squad to Toronto to kill her. They fail in their first attempt as Kats apartment turns into an inferno. Thinking that she is dead they leave. Having escaped their attack, Kat and her family go into hiding. She befriends Raini, a very recently retired M-CI agent and as trained investigators, together they set out to prove Kat's innocence, while on the run from the killers, and the international police.
Eventually Hedda realizes that Siggi had been misleading her and that he would send his own hit team to eliminate her. Turning her anger on Siggi she escaped his killers and goes after him. Like true detectives, Kat and Raini follow Hedda's trail from Spain to Switzerland, where Hedda has gone to punish him for his treachery. Hedda discovers Siggi body and thinks Anita has killed him. Kat and Raini believe that Hedda did it. That leads to a thrilling and terrifying car chase over an urban mountaintop. After a spectacular crash they catch up to Hedda. She is severely injured and dies before she is made to confess.
Now blamed for not only Hedda's death but Siggi's as well, the exhausted and frightened women are on the run again. This time they go to England to find sanctuary. There are unaware that the European authorities have at last discovered the truth of Kat's innocence and have called off their hunt. Wolfson's kill squad redoubles their efforts and continue the pursuit. The English police and MI5 discover that the real killer has been found, so Kat is no longer blamed for Hedda's crimes. But they are told by Wolfson that they must keep Kat's innocence a secret, sighting American security concerns. The chase continues. Soon Kat and Raini are captured in a small town where the local police don't know that she has been cleared. In custody Kat and Raini are sent to London where Kat will be tried for the murder of a London man also killed by Anita Franco's imposter.
On route they are waylaid by the killers in a stolen American helicopter. Tragically Raini is murdered, but Kat overcomes her would be killers and escapes in the helicopter. Intercepted by the British Navy's Coastal Patrol for flying the stolen American Helicopter into British airspace, Kat is held for questioning. The remaining members of the kill squad track her down to the RNAS Yeovilton and break in to finish the job. She manages to escape that crisis and is then sent to London. Cleared of all charges she is released and looks forward to continuing her peaceful life with Deacon and Sara. But when she and Deacon come face to face with Edward Jäger still very much alive in their hotel lobby. Kat's dream of the normal life comes to an end.
