The Man from the Diners' Club [1963] [DVD]

Meek credit card company clerk Ernest Klenk (Danny Kaye) is feeling the pressure of demanding coworkers, new computers and an upcoming wedding. This stress leads to a big mistake -- the accidental approval of a credit card for mobster Foots Pulardos (Telly Savalas), who is planning to flee to Mexico with his girlfriend, Sugar Pye (Cara Williams), in order to avoid criminal charges. When Klenk tries to fix his mix-up, he gets dangerously involved in Foots' scheme.