During a major snow storm, Transcon Airways Flight 602, Boeing 727 airliner piloted by Captain Pete Douglas (David Janssen), First Officer Stan Burkhart (Christopher George) and Second Officer Mike Fuller (Don Meredith) on a flight from Los Angeles to New York, makes a scheduled stop in Salt Lake City. Greco (Marjoe Gortner), a two-time killer in the custody of Sam Riese, a Federal Marshal (Broderick Crawford) comes aboard. Among the passengers are Burkhart's girlfriend, nurse Susan McKenzie (Margaret Blye) and Joseph Mannheim (Ray Milland) a disillusioned and possibly disgraced medical doctor drowning his problems with scotch. Captain Douglas has a family emergency that is making him anxious to return home as soon as possible.