Overhearing his parents Stephanie and David Carver having a heated argument, young Justin Carver (Cole Sprouse) retreats to his bedroom. A few minutes later, Justin peeks downstairs, only to see his mother Stephanie (Connie Sellecca) locked in a warm, romantic embrace with none other than Santa Claus. Unaware that mom's hirsute "lover" is actually his own father, David (Corbin Bernsen), who has dressed up as Santa in hopes of getting back in Stephanie's good graces, Justin is convinced that his parents' marriage is on the rocks -- just like the recently shattered union of his best friend's parents. Further convinced that jolly old Saint Nick is the cause of all the marital disharmony, little Justin goes on a one-boy vendetta, physically assaulting every department-store and sidewalk Santa who crosses his path. Very loosely based on the 1949 hit song of the same name, the made-for-TV I Saw Mommy Kissing Santa Claus first aired December 9, 2001, on the PAX network.