The Temples meet the Fergusons when travelling home from New York, but are later told that the Fergusons' son Richard has been murdered at his university. The only leads are a postcard signed "Jonathan" and Richard's missing signet ring.

Swinging between London and Geneva, Paul Temple and Steve are involved in a case that involves finding the answer to one vital question: is Carl Milbourne, thought to have perished in a car accident, still alive? There are those who are determined to stop the Temples discovering the truth. And Temple's own life is in danger.

On a boat trip from the fishing village of Downburgh, Paul and Steve Temple are shot at and later the boatman dies in a cliff-top fall. Back in London, the daughter of the head of M.I.5. has disappeared and it soon transpires there is a connection.

Returning from America by ocean liner, the Temples meet wealthy Sam Portland whose UK agent Hubert Greene has received messages about Portland's past from a private detective called Madison. But Portland dies on board, and Temple is left to unravel a case involving international counterfeiters and the clue of a coin on a watch-chain.

Sir Graham Forbes of Scotland Yard often calls upon Paul Temple to help with his latest unfathomable case...

Eine Produktion des BBC von 1961