Goofs

When Grandpa is trying to get Herman to take the "sea-sick" pill, he is wearing gloves. When he, himself, takes the wolf pill by mistake, his left hand starts to change and he is no longer wearing a glove on that hand, but he is still wearing a glove on the right hand.

When Herman goes to the kennels where Grandpa is being held as a wolf, he unhooks the chain with the "No admittance" sign. He is then interrupted by a ship's steward, who replaces the chain on the hook. Herman then trips over the chain when he goes to re-enter the kennels. When the other ship's steward races out of the room after being scared by Herman, the chain is unhooked again.

When Roger Moresby is knocked out, taken the small building, and tied up, he is wearing a helmet. When he tries to escape, he is no longer wearing the helmet.

It is mentioned that Freddie Munster's father disowned him so the title "Lord Munster" would pass to Herman. In English peerage, a title passes onto the next in line of succession regardless of the previous holder's wishes. Only an Act of Parliament may remove an heir. Freddie's father could leave all the money and land to Herman, but the title would go to Freddie.

The SS United States is depicted as having wooden doors and furniture; neither of these existed aboard the real liner. The designer of the ship was a fanatic about fire safety, and virtually no wood was aboard. Additionally, the portholes in the cabins were sealed, whereas in the movie, they are shown open.

British titles are inherited by the next in line. Even if Freddie had murdered Herman, Eddie, Herman's son, would have inherited the title. Besides, if Herman was put together in Germany, he was not genetically related to the English Muster Lords.

Makeup is missing from the back of Eddie's ears and neck, as well as Lily's palms.

The masked stunt driver who plays "The Griffin" is obviously a male (The Griffin in actuality was later revealed to be Millie, the Barmaid), as in closeups of the hands on the wheel the viewer can see that the quite hairy and masculine wrists of the driver.

Obvious stunt doubles for Lily and Grandpa in the long shots of them riding the horses. The makeup and hair for Grandpa's double is a bit more exaggerated.

When Herman is racing towards the oil slick near the finish line, the Drag-U-La car begins to spin out before the car reaches the oil slick. By the time the car reaches the oil, it is already sideways, and the rear wheels hitting it are used to propel oil into the air.

The race cars are all left-hand drive cars. While it is logical that the Drag-U-La car would be left-hand drive, since this was supposed to be England, at least some the others should be right-hand drive cars.

The background scenery of the race is obviously Southern California, not England. At least there must have been a good amount of rain before this movie was filmed, all the vegetation is green.

Freddie complains, "I'm Lord Munster, not HIM!" Lady Effigie explains that Freddie should have used the pronoun HE because "the objective pronoun always takes the nominative case". While she is right that Freddie should have used the pronoun HE, her explanation should have been, "When the predicate pronoun refers to the subject, the pronoun takes the nominative case". In fact, most pronouns in the predicate of a sentence are in the objective case, not the nominative case.