Batman & the Joker. The deadly duo the deluxe edition

"The Joker will go to any lengths to get Harley Quinn back after she is abducted by a strange culprit. But who? Mysterious, Joker-like monsters are stalking the streets of Gotham, collecting severed heads. But why? Jim Gordon is missing, and after receiving a package containing a bloody piece of Gotham's commissioner, Batman knows he must be willing to do anything to save him. But how? When The Joker proposes an uneasy alliance with Batman, the a...