Red Square, 1985. The naked body of a young man is left outside the walls of the Kremlin: frozen solid - like marble to the touch - and missing the little finger from his right hand. A week later Alex Marston, the headstrong 15-year-old daughter of the British ambassador, disappears. Army intelligence officer Tom Fox, posted to Moscow to keep him from telling the truth to a government committee, is asked to help find her. It's a shot at redemption. But Russia is reluctant to give up the worst of her secrets.

A Russian defector is found brutally murdered in a London hotel. Only four people knew he had turned - the four most important and powerful figures in Whitehall. There's only one conclusion - a mole has infiltrated the highest levels of the nation's security. Operating in secret from within Westminster's darkest corners, former spy Solomon Vine must uncover the traitor. Because Britain's future hangs in the balance. And with it the fate of the whole world.

Only she knows the truth. Only he can tell the world. Vienna, 1946. A brilliant German scientist spirited out of the ruins Nazi Europe in search of a new life. Moscow, 1964. A rising star of the British diplomatic service whose job is not what it seems. London, the present day. A once promising academic offered an opportunity to seal his place in history. Their stories, their lives, and the fate of the world, are bound by a single document: The Scarlet Papers. The devastating secrets contained within teased by a brief invitation: Tomorrow 11AM. Take a cab and pay in cash. Tell no one.

Clive Franklin, a Russian language expert in the Foreign Office, is summoned unexpectedly to Moscow to act as translator for the British Prime Minister. His life is upended when he discovers that his former lover, Marina Volina, is the interpreter to the Russian President. Together they will try to stop the attack that could paralyse communications and collapse the Western economy.

When disgraced spy Solomon Vine's friend and rival Gabriel Wilde vanishes without trace, it's only Vine who might be able to discover what has happened to him. A single missing file holds the key. That, too, is gone. But its contents, Vine is told, are incendiary. There were few Wilde could trust. And being one of them appears to have fatal consequences. But as Vine's off-the-books investigation begins to reveal the shocking truth, he realizes there's much more at stake than one man's life.

July 1940. As Britain braces itself for invasion, ex-Tommy and safecracker Bill O'Hagan is glad to have escaped the battlefield. But when a job goes wrong, he finds himself forced to serve his country once more. Spurned by his government and fearing for his life, the Duke of Windsor flees to Portugal with the woman for whom he abdicated the throne, Wallis Simpson. As a web of Nazi trickery threatens to ensnare him, his fate and the fate of Britain rest on one man. 

In Baku, Azerbaijan, CIA operations officer Daria Buckingham is arrested for a heinous crime. Her former boss, retired CIA station chief Mark Sava, is sure she’s innocent and tries to help her out - landing him in the middle of the new Great Game, an espionage war over oil that has China, Iran, and the United States clawing at each other’s throats. Back in Washington, DC, Colonel Henry Amato, assistant to the US national security advisor, is keeping a close watch on the situation.

London 1929. Very much not a land fit for heroes. Frenchie knows his occasional work for MI5 serves only the ruling classes. But he needs to feed his children. Scruples died in the trenches. When Ramsay MacDonald, Britain's first Labour prime minister, is blackmailed by a former lover, Frenchie must go to Paris to buy her silence. It is clear there are many people who would see MacDonald fall—the Conservatives, their friends in the press, even some of his own colleagues. But his own secret service? When Frenchie hears the other side of the story, everything changes.

Inspector Max Betancourt is working a new beat, one he didn’t ask for. Following the disappearance of his wife, his life and career have fallen apart. Once a rising star of Singapore CID, Betancourt has been relegated to the Marine Division, with tedious dockyard disputes and goods inspections among his new duties.

Lyndsey was once a top handler in the Moscow Field Station, where she was known as the "human lie detector" and praised for recruiting some of the most senior Russian officials. But now, three Russian assets have been exposed - including one of her own - and the CIA is convinced there's a mole in the department. With years of work in question and lives on the line, Lyndsey is thrown back into life at the agency, this time tracing the steps of those closest to her.