This is the first time that Batman appears in a cowl in a color other his usual dark blue, when the Mad Hatter turns his cowl pink.
This episode marks the only time that the George Barris replica Batmobile (#4) appears on the show. It is mostly obscured but still visible in the bat cave.
This is the second consecutive story in which someone refers to Robin as "Wonder Boy" (the first being the Sandman in "The Sandman Cometh").
Partially based on a comic book story published in Detective Comics 230.
The Mad Hatter claims that the bearskin he possesses was taken from a British Army Foot Guardsman at the very moment he was trooping the colour for the King. The annual Trooping the Colour ceremony is a massive parade of the United Kingdom's most senior Army units, held in June to honour the Sovereign's Official Birthday. At the precise moment during that the colour is trooped, the Ensign bearing the colour is surrounded by over a thousand of the UK's most elite troops, two hundred horses, and at least three hundred musicians, plus the Sovereign and the entire Royal Family.