When Mr. Freeze comes walking in as a head, Batgirl's neck is showing and part of her costume is suddenly missing. It's her bare neck out of her costume.
(Tim failed a civics test at school)Bruce: You don't know the first thing about the American justice system, do you?
Tim: I know it's bogus.
Bruce: And how did you come to that well, thought-out conclusion?
Tim: Watching you. You don't exactly follow the rules of due process.
Bruce: I...how did you do on your math test?
Bruce: (on TV) As my father once told me, 'Those who have the most, must give the most.'
Mr. Freeze: Those who have the most also have the most to lose, Mr. Wayne.
At the end of this episode, Mr. Freeze is supposedly dead. However, he appears in the future in the Batman Beyond episode, "Meltdown." This episode sets up the storyline for it.