Factual error: Nick tells fellow vampire Aristotle, "You still owe me for that time at the Battle of Hastings." Nick was brought across in 1228, or so the intro told us every week. The Battle of Hastings, as any British school kid knows, was fought in 1066, over 100 years before Nick's mortal birth. (00:29:30)
Jean G
Factual error: Batman is in Japan and tracks down Kyodai Ken by using Caller ID, which returns a seven-digit "555" number. Telephone numbers in Japan have 8 digits.
Captain Defenestrator
Factual error: When Charles Barkley says "Welcome to the NBA" after dunking on Mark, the ceiling shown above Barkley is way too low to be the ceiling for Haas Pavilion at UC Berkley where the game is being played. It only appears to be about 30 feet high.
Phaneron
Factual error: In many episodes, cars which are said to be owned by a character have a Certificate of Fitness on their windscreen. Private passenger vehicles in New Zealand under 3.5 tonnes have a Warrant of Fitness, not a Certificate of Fitness. This means these cars are most likely rentals.