Learning of a plot to attack a major peace conference in Scotland, MI5 officer Liz Carlyle follows a series of elusive clues only to realize that the threat is much greater than anticipated and has a potential to permanently destabilize the Middle East.

In 1940, eighteen-year old Juliet Armstrong is reluctantly recruited into the world of espionage. Sent to an obscure department of MI5 tasked with monitoring the comings and goings of British Fascist sympathizers, she discovers the work to be by turns both tedious and terrifying. But after the war has ended, she presumes the events of those years have been relegated to the past forever. Ten years later, now a radio producer at the BBC, Juliet is unexpectedly...

At a tracking station in Virginia, U.S. Navy officers watch in horror as one of their communications satellites plummets into the Indian Ocean and panic spreads through the British and American intelligence services.
When a Russian intelligence officer approaches MI5 with vital information about the cyber sabotage, he refuses to talk to anyone but Liz Carlyle. But who is he, and how is he connected to Liz?
Is this a Russian plot to disable...

"Two years ago, a hostile Prime Minister launched the Monochrome inquiry, an auditing of the British Secret Service "to investigate historical over-reaching." Monochrome's mission was to ferret out any hint of misconduct by any MI5 officer--and allowed Griselda Fleet and Malcolm Kyle, the two civil servants seconded to the project, unfettered access to any and all confidential information in the Service archives in order to do so. But MI5's formidable...

"British intelligence is in a state of panic. Cracks are appearing, or so a run of disciplinary cases would suggest. To cap it all, a retired MI5 officer collapses, the victim of what looks like a Russian poisoning. Leonard Flood is ordered to investigate--and quickly. Notorious for his sharp elbows and blunt manner, Leonard's only objective is to get the job done, whatever the cost. But when the trail leads him from the suburbs of London to a remote...

The Cold War heats up when a KGB defector exposes Operation Glass, a potentially devastating Soviet plot to activate sleeper agents across the UK. The charismatic but paranoid head of MI-5, known simply as 'Daddy', assembles a secret committee of spies and intelligence officers to investigate. They're the only colleagues he trusts in a world of double agents and lies, but has he chosen well?

"Lachlan Kite is a member of BOX 88, an elite transatlantic black ops outfit so covert that not even MI6 and the CIA are certain of its existence--but even the best spy can't anticipate every potential threat in a world where dangerous actors lurk around every corner. At the funeral of his childhood best friend, Lachlan falls into a trap that drops him into the hands of a potentially deadly interrogation, with his pregnant wife, also abducted, being...

Johnny Worricker is a long-serving MI5 officer. His boss and best friend Benedict Baron dies suddenly, leaving behind him an inexplicable file, threatening the stability of the organization. Meanwhile, a seemingly chance encounter with Johnny's striking next-door neighbor and political activist Nancy Pierpan seems too good to be true. Johnny is forced to walk out of his job, and then out of his identity to find out the truth.

Worricker after the director of MI5 dies. A conspiracy to turn control of MI5 over to the Prime Minister leads Worricker to the islands known as the Turks & Caicos, where he is persuaded by the CIA to deal with a group of ambiguous Americans attending a high-level conference. At the same time, an old girlfriend, Margot Tyrrell, is being asked to betray her boss in London in order to establish an illicit connection between the prime minister and dark...

When a terrorist escapes custody during a routine handover, Will Holloway must team with disgraced MI5 Intelligence Chief Harry Pearce to track him down before an imminent terrorist attack on London.