There is an apparent in-joke when Hurd Hatfield compares Joan Caulfield's Mathilda character to her portrait, saying that she hasn't changed, but her portrait has, a clear reference to his signature film, "The Picture of Dorian Gray."
During Oliver Keane's accident scene, he is seen driving a grey car at first, but when he skids off the road and tumbles down the hill, it is suddenly black.