Time Table (1956) on Netflix

Plot summary

Paul Bruckner, a surgeon whose license was revoked, boards a train crossing Arizona as Dr. Sloane, accompanying a fictitious patient. In the baggage car he opens the physician's bag, blows the safe and takes a $500,000 cash payroll. He and the man playing the patient, supposedly infected with polio, leave the train at a small town with a hospital, far from any scheduled stop, and drive off in an ambulance. The robbery goes unnoticed until the train reaches Phoenix hours later. The insurance company hands the case to claim investigator Charlie Norman, whose Mexico vacation with his wife Ruth is postponed. He works it with Joe Armstrong, a veteran railroad policeman and a friend.