Jonas is a British spy out in the cold. When his father is kidnapped by ISIS in Syria, he heads to Beirut and recruits a Swiss priest named Father Tobias. Tobias agrees to travel into the heart of the Islamic State and inform the kidnappers that Jonas is willing to negotiate for his father's life. British intelligence agents try everything in their power to stop Jonas, and he finds himself tested to the limit as he fights to keep the negotiations alive.

Things are looking bad for disgraced spy August Drummond. In emotional free fall after the death of his wife, fired for a series of unprecedented security breaches that saw him labelled a traitor...and now his neighbour on the flight to Istanbul won’t stop talking. The only thing keeping him sane is the hunch that there’s something not quite right about the nervous young man several rows ahead - a hunch that is confirmed when August watches him throw away directions to an old European cemetery seconds before being detained by Turkish police.

British spy Leonard Flood is asked to investigate the poisoning in London of Willa Karlsson, a retired British secret service vetting officer suspected of being a Russian agent. British intelligence is terrified by the possibility that Moscow poisoned her upon her retirement since she was no longer useful to them. When Leonard discovers that he is also a suspect in the investigation and that Willa's story is less a story of betrayal than one of friendship, he must decide whether to hand her to her masters or to help her to escape.