Commissioner Gordon mentions people "who came to this Batcave and never left". This is a reference to another Riddler henchwoman, Molly, who was killed when she fell into the atomic pile in Smack in the Middle (1966).
Pauline mentions that her lawyer's name is Oliver Wendell, a reference to Associate Supreme Court Justice Oliver Wendell Holmes, who served on the bench from 1902 to 1932.
Last appearance of Francis X. Bushman as Van Jones, a collector of silent movies. Bushman himself was a star of many early silent films.
When the Riddler has Robin on the ledge of the building, Robin's blindfold moves from just above his nose to completely covering it, depending on the shot.