The April Fools (1969)

Newly-promoted if none too happily married Howard Brubaker leaves a rowdy company party early with the stunning Catherine, whom it turns out is herself unhappily married — to the boss. They spend an innocent night in New York becoming more and more attracted to each other, so that when Catherine announces she intends to leave her husband and return to Paris Howard asks to go along too.
Hank Moonjean, Stuart Rosenberg, Ted Zachary, Betty Crosby, Charles Ziarko
Jack Lemmon, Catherine Deneuve, Peter Lawford, Jack Weston, Myrna Loy, Charles Boyer, Kenneth Mars, Melinda Dillon, Harvey Korman, Sally Kellerman, Gary Dubin, Janice Carroll, Dee Gardner, David Doyle, Susan Barrett, Tani Guthrie, Nancy Howard, Tom Ahearne, Don Ames, Poupée Bocar, Marlys Burdette, Yvonne D’Angers, Kathryn Janssen, Sharon Johnson, Chester Jones, Kenner G. Kemp, Sherry Lansing, Esther Ying Lee, Todd Mason, Arlene Parness, Murray Pollack, Frank Raiter, Tony Regan, Felix Silla, Owen Song, Lisa Todd
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