Adolphe Menjou is John Mannering, the high profile black sheep of a Barrymore-like family of theatrical legends. The aging, alcoholic womanizer is amused by the arrival of long lost daughter Kay (Andrea Leeds).Determined to become a star on her own merits, Kay has adopted the last name of "Martin." Mannering approves of Kay's high-minded actions and agrees to keep his daughter's identity a secret. As cruel result, Mannering and Kay become an item in the gossip columns as they are routinely seen together in public while refusing to explain their May-December relationship.Edgar Bergen and his tuxedoed smart mouthed dummy, Charlie McCarthy, are Kay's best friends. Their uproarious patter is the nearly constant commentary of the romantic intriguearound them.Photographed by remarkable German cinematographer Karl Freund and featuring Eve Arden as the "other woman" who also wants to sit on Edgar Bergen's lap, Letter of Introduction is a sincere, deftly-handled tapestry of fantastic romanticemotions.