While on assignment in Monte Carlo, Steve finds an American intelligence agent who has been severely beaten and robbed. Steve agrees to undertake the agent's assignment - retrieving a roll of film with incriminating photographs of a corrupt politician.
On an airplane Steve meets two children traveling alone who refuse to give their last name. When their aunt fails to meet them at the airport, Steve takes pity on them and allows them to stay in his hotel room. The children's aunt finally arrives, but Steve learns too late that a Romanian industrialist has fled to Crete with a large sum of money and the "aunt" is actually a communist agent who plans to use the children as hostages to force the defector to return behind the Iron Curtain.