American playboy Bernard Lawrence (Tony Curtis) has cleverly designed a system using the airline timetables to keep going three affairs with flight stewardesses. However, his life soon starts to descend into a shambles after the arrival of a friend, Robert Reed (Jerry Lewis), and a dreaded change to the flight order, whereby it becomes increasingly difficult to keep his three fiancées apart. Written by David Gibson Living in Paris, journalist Bernard has devised a scheme to keep three fiancées: Lufthansa, Air France and British United. Everything works fine as long as they only come home every third day. But when there's a change in their working schedule, they will be able to be home every second day instead. Bernard's carefully structured life is breaking apart.