Nine passengers board a commercial flight from Los Angeles to Panama City: wealthy Judson Ellis and Alice Melhorne, eloping because their parents disapprove; an elderly couple, Professor Henry Spengler and his wife Martha; Tommy Mulvaney, the young son of a gangster, and his escort, gunman Pete; Peggy Nolan, a woman with a shady past; and Vasquez, an anarchist being extradited and facing a death sentence for killing a high-ranking politician, and his guard, Crimp. The crew consists of pilot Bill, co-pilot Joe Brooks, and steward Larry.