Joker: Jingle bells, Batman smells. Robin laid an egg. The Batmobile lost a wheel and the Joker got awaaaaaaaaayyyyy.
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.
The voice of Simon Trent/Grey Ghost is provided by Adam West. Adam West portrayed Bruce Wayne/Batman in the 1960's TV show Batman.