Dean Jones and Suzanne Pleshette star in this Walt Disney family comedy as Mark and Fran Garrison, a dog-loving couple with different tastes in canines. The story begins with their dachshund, Danke, giving birth to 3 puppies. One day, gentle veterinarian, Dr. Pruitt convinces Mark to take a runt Great Dane puppy home with him as a gift. His Great Dane that same day had a large litter of puppies and didn't have enough milk for all of them. Mark agrees and The Great Dane, named Brutus, grows up with the tiny pups; convinced that he's also a dachshund. Brutus' confused identity sets the stage for a number of mildly comic bits lead by the mischievous dachshunds--he chases a policeman up a tree, destroys Mark's studio with paint splattered, and ruins a garden party in a topsy-turvy way. Fran finally tells Mark that Brutus has to go, but changes her mind when Brutus saves Fran's favorite dachshund puppy, Chloe, from a scrap heap. Mark and Fran enter their dogs in a dog show with Brutus meeting others of his breed. He notices a female Great Dane and stands at attention. He goes on to win two blue ribbons. Brutus finally finds out what its like to be a Great Dane.
- Dean Jones - Mark Garrison
- Suzanne Pleshette - Fran Garrison
- Charlie Ruggles - Dr. Pruitt
- Kelly Thordsen - Officer/Sgt. Carmody
- Parley Baer - Mel Chadwick
- Robert Kino - Mr. Toyama
- Mako Iwamatsu - Kenji
- Charles Lane - Judge
- Gil Lamb - Milkman
- Dick Wesson - Eddie (voice looped by Paul Frees)
- Director - Norman Tokar
- Producer - Walt Disney
- Co-producer - Winston Hibler
- Set Designer - Frank R. McKelvey
- Costume Designer - Chuck Keehne
- Art Director - Marvin Aubrey Davis
- Costume Designer - Gertrude Casey
- Makeup - Pat McNalley
- Consultant/advisor - Glenn H. Randall, Jr.
- First Assistant Director - Tom Leetch
- The title references the literary fairy tale, The Ugly Duckling.
- Both animals were being raised by a different species.
- They were neglected by their respective foster family.
- They discovered who their species really are.