After a diamond heist gone awry, the Joker makes his escape by car, with an anxious Harley Quinn at the wheel and Batman in hot pursuit. With a clear shot at the Batmobile, Joker commands a frazzled Harley to give him a gun, but when she hands him the first gun that she grabs out of a bag, it turns out to be a harmless pop gun. Although Harley manages to shake the Batman of their tail, Joker has had enough of her. He kicks Harley out of his gang for good. Heartbroken, Harley is nevertheless determined to make her own way in the criminal underworld. So she returns to the museum to steal the diamond all by herself. However, Harley's freelance plans get skewed when the museum alarm sounds--only they are set off by Poison Ivy, who is pulling off a heist of her own by stealing some rare plants from the labs. Taking the diamond anyway, Harley and Ivy work together to evade the army of police that has descended on the museum.

Realizing that they compliment each other very well, Harley and Ivy decide to team up. Their first job together is robbing an exclusive all-male club of its funds. It isn't long before the women embark on a wildly successful crime spree, with the Gotham City press dubbing them the new Queens Of Crime. Of course, Batman soon takes notice of this new and unusual threat to Gotham City and begins to follow their trail--however, the Caped Crusader doesn't know that he has a rival who is also hunting Harley and Ivy down as well. The Joker is desperate for a reunion with Harley…more to the point, he would love to get his hands on the loot that Harley and Ivy stole.

This is a fun, much-needed change of pace episode that works on many levels. Written by Paul Dini, "Harley and Ivy" deftly explores Harley's gun moll-like relationship with the Joker, and how he keeps control over her through subtle manipulation of her self-esteem, which is pretty much zilch. It is only when Harley teams up with Ivy that she becomes a full-fledged equal partner, and she fully blossoms, with her scenes with Ivy having a great Thelma and Louise-type vibe. While one of the episode's creators mentions on the commentary track that "Harley And Ivy" is for the girls, everybody can enjoy it. "Harley And Ivy" maintains its feminine empowerment charge without getting too preachy thanks to a healthy dose of humor (the girls' reaction to a carload of randy guys trying to pick them up is a classic moment), and the scenes of Harley and Ivy lounging around their lair while scantily clad certainly don't hurt, either!