Batman & the Joker: The Deadly Duo — DC Comics
Issue: #5
When the Deadly Duo’s investigation brings them into the catacombs under Gotham, Batman and The Joker’s adventure becomes a trip into hell. If you thought this series had already shown you its horrors, get ready for a descent into the heart of darkness as Batman and The Joker’s true enemy is revealed.
Creators: Gary Frank, Whilce Portacio, Alex Sinclair, Marc Silvestri, Brad Anderson, Troy Peteri, Arif Prianto, Michael Spicer, Daniel Warren Johnson
Characters: Dick Grayson, Harley Quinn, Batman, Joker, James Gordon, Barbara Gordon, Alfred Pennyworth