After finding himself alone in a strange city in America, Harry meets a few people that he decides he likes. Dark!Harry, ALittleCrazy!Harry, tomarry later on. Crossover involving the Joker and Harley Quinn.

Joker never understood why his brother took destiny and prophesy so serious (or anything for that matter. He really needed to smile more). The future wasn't set in stone after all. Besides, wasn't it much more fun to corrupt the child, shape him to their image of insanity and chaos, instead of killing him? He certainly thought so. Insane!Harry, Dark!Harry, Adult content/Slash later

Batman sends his young son to Hogwarts to keep an eye on The Boy Who Lived.

If Harry had detective vision and the dursleys were killed... What would happen?

Actually takes place in Batman: Arkham knight. Hemrione comes to Gotham to visit her Cousin Dick Grayson, and ends up falling for Bruce Wayne right before Scarecrow makes his threat to Gotham. (Little OOC not to much.)

Auror Harry Potter is sent to Arkham City to go undercover and infiltrate the Joker's gang. His status as a wizard is soon discovered by Harley Quinn, and she and the Joker begin to develop an obsession with their pretty green-eyed magician. Het and Slash.

What if Lily and James weren't Harry's real parents. What if his real parents are none other than Harley Quinn and the Joker! Watch as Harry ditches his previous name in order to become Harrison Quinn - The New Clown Prince of Crime! Set during the end of 4th year and read to discover the surprise in the story. Working on Sequel.

Two years have past since the return of Harrison Quinn and Gotham hasn't been the same since. With three insane clowns, the Dark Knight has been busy training the newest member of the Bat Family: Stephanie Brown. What happens when she meets the New Crime Prince. And how will she react when she learns of Harrison's dark past?

One-shot: after Sirius dies, Harry snaps and makes his way towards Gotham where secrets of his past are revealed by his transformation: say hello to the new Clown Prince of Crime: Harrison Quinn!

Harry's aunt and uncle throw him into Arkham City on his eighth birthday after revealing his parents' murder to him. Locked in a city with murderers, rapists and the likes of Joker, Two-Face and Penguin, he latches onto the first kind face he meets, Pamela Isley. But, just what does Professor Hugo Strange have up his sleeve in wait for the young wizard? T for language.