A man lies dying in a hospital in upstate Vermont. The nurses know only that he is an academic at a nearby university but they have been instructed to call the FBI should anyone visit their patient.

News of this suspected Russian illegal soon reaches MI5 in London where Liz Carlyle has been contacted by a top secret source known as Mischa who is requesting a clandestine rendezvous in Berlin.

Meanwhile, in Brussels a Russian sleeper agent who has lived undercover for years is beginning to question his role, while suspicions have been roused about a boarding school in Suffolk that has recently changed hands in mysterious circumstances.