The amusement park where Stevens and Jones spend an afternoon was Pacific Ocean Park, elements of which still exist today as part of Southern California's Santa Monica Pier.
The song 'Devotion," originally composed by Max Steiner and sung by Irene Dunne in the film Consolation Marriage (1931), was recycled for the soundtrack of this film, along with one of the principal motifs from A Summer Place (1959), utilized as the main theme in the love scenes between Connie Stevens and Dean Jones.
Some of the interior sets (particularly the hallway with the stairs and the study) are recycled from My Fair Lady (1964). The wallpaper is distinctive, as well as the lower landing on the staircase.
Partially filmed on location at Benedict Castle in Riverside, California.
William Conrad: Look for this film's director, character Actor William Conrad, in the amusement park scene. When Cassie and Val stop in front of the wall of mirrors, Conrad is already standing there. He smiles at them as he walks past them.