Harley Quinn #21 2002

Harley Quinn #21 (DC) features Harley confronting Madame Macabre, who blames her for Arkham. She also battles Devani Kage, a "Bat-Lady" from the future, revealing alternate timelines. The issue develops Red Tool's intense obsession with Harley and sets up a visit from her unsuspecting parents. A "Harley Loves Joker" backup story shows Harley running errands for the Joker and scouting a new hideout. This issue is notable for advancing key character arcs and introducing new elements.