This is a tale of blackmail and political intrigue involving the Czechoslovakian Security Services during the Cold War and a future British prime minister. It is a spy story in which John Le Carre's 'Smiley's People' meets the political thriller 'House of Cards'. It centres on an allegation made by the Czech defector Josef Frolik in a book published in the 1970s after he had fled to the United States. Frolik claimed that his colleagues had hatched an unsuccessful plot to blackmail the upcoming politician and future Conservative prime minister Edward Heath in the 1960s. Heath denied all knowledge of it at the time and the story was forgotten after Margaret Thatcher took over the Conservative Party leadership and went on to become prime minister.
Now, more than forty years later, the BBC's Security Correspondent Gordon Corera attempts to unravel the truth behind what became known as 'The Heath Caper'. Nothing is what it seems. Corera travels to Prague where he talks to the man who was said to be behind the plot - Jan Mrazek, now in his eighties, a former Major in the Czechoslovakian intelligence service during the Cold War.
Mrazek ran one of the most successful Czech agents in Britain when he worked at his country's embassy in London, mixing with leading politicians and British trade unionists. His personal file in the security service's archives is now open to the public and boasts of his success in gathering intelligence for his communist masters and recruiting new agents willing to betray their country. But there is no mention of the plot. Mrazek insists that Frolik made it all up, urged on by right wingers who wanted to discredit Heath in order to give Margaret Thatcher free rein in her bid to become PM.
Who, then, is telling the truth?