Betty Kane was the Golden Age Batgirl. The character of Barbara Gordon was created to play Batgirl in the Batman TV show. Superpowered teen Charlie Gage-Radcliffe briefly donned the Batgirl costume after Barbara was injured, but soon changed her name to Misfit. Laurel Lance is the Black Canary.

Schwarzenegger played the cold-hearted villain Mr. Freeze to George Clooney's Batman.

Azrael (Jean-Paul Valley) plays a pivotal role in the "Knightfall" story arc (1993-1994), in which he stands in as Batman after Bruce Wayne is defeated and paralyzed at the hands of Bane.

Cassandra Cain is the daughter of assassins David Cain and Lady Shiva. She was deprived of speech and human contact during her childhood as conditioning to become the world's greatest assassin. She first appeared in Batman #567.

"The Dark Knight Returns", written by Frank Miller, tells an alternate history of Bruce Wayne, who at 55 years old returns from retirement to fight crime and faces opposition from the Gotham City police force and the United States government.

Catwoman is an accomplished jewel thief. Known for having a complex love-hate relationship with Batman, she has been the Caped Crusader's most enduring love interest, and even fathered a child with him on Earth-2.

Harley Quinn met the Joker while working as a psychiatrist at Arkham Asylum. During therapy sessions, she fell in love with him and eventually helped him escape.

The Joker possesses no superhuman abilities, instead using his expertise in chemical engineering to develop poisonous or lethal concoctions, and thematic weaponry, including razor-tipped playing cards, deadly joy buzzers, and acid-spraying lapel flowers.

Calendar Man is known for committing crimes that correspond with holidays and often wears costumes to correlate with the date of the designated crime. Calendar Man first appeared in Detective Comics #259.

In Batman #114, a circus ape named Mogo follows Batman and Robin back to the Batcave, decides to try on one of Batman's spare capes, and helps the Dynamic Duo track down a thief.