Harley Quinn (2000-2004) #21

Harley is trapped in the ultimate prison by a demonic fellow whose name begins with the letter "E." She enlists the help of some familiar--if unexpected--faces in a massive attempt to regain her freedom. Harley's got a gaggle of unusual superhumans on her side, but it ain't easy to come back from...well, wherever, especially with a bounty hunter gunning for your head.