A ring falls into the pants cuff worn by teenager Wilby Daniels (Tommy Kirk) while he is visiting a museum, and, not noticing, he carries it home with him. The ring’s ancient spell turns him into a huge shaggy dog, identical to the one owned by his pretty new neighbor, Franceska (Roberta Shore). Wilby’s father (Fred MacMurray) is allergic to dogs, so Wilby hides out in Franceska’s house, where he overhears Franceska’s father plotting to steal secret missile plans. Still a dog, Wilby has to figure out a way to foil the spies and save Franceska.
This low-key fantasy/comedy is a long-time family favorite, and children love to see the dog driving the car and wearing pajamas.
The 1976 sequel, The Shaggy D.A. was followed by more two made-for-television sequels starring Harry Anderson.