Solo and Illya board the Adriatic Express train on New Year's Eve to intercept Madame Nemirovitch, a THRUSH agent who is carrying a chemical that is capable of stopping the reproductive process. Eva, a young girl who delivers a message to Madame Nemirovitch as the train leaves, is caught on board. Throughout the evening, the THRUSH agent and Solo and Illya engage in a battle of wits as the train speeds along its route. (thetvdb.com)