One idea could be that Deadpool and Harley Quinn team up to take on a common enemy, like a supervillain who's causing chaos in Gotham and also has a connection to one of Deadpool's foes. They could start off bickering because of their very different personalities but gradually learn to work together.
Maybe there's a multiverse plot where Deadpool somehow ends up in Harley Quinn's world. Harley is initially suspicious of him but then realizes he can be a useful ally in her fight against the Joker. They could have some really wacky adventures as they try to find a way to get Deadpool back to his own universe.
One plot idea could be that Deadpool and Harley Quinn team up to take on a common enemy, like a new super - villain in Gotham who has a connection to some of Deadpool's foes. They could start off not getting along because of their different personalities, Deadpool's fourth - wall - breaking and Harley's chaotic - cute nature. But as they face challenges together, they learn to work as a team and even become friends.
One idea could be that Harley Quinn and Deadpool team up to take on a common enemy who has been causing chaos in both their worlds. They could start off as reluctant partners, with Harley being annoyed by Deadpool's constant chatter and Deadpool finding Harley's craziness a bit much at first. But as they fight side by side, they learn to appreciate each other's skills and form an unlikely friendship.
One idea could be that they are both transported to an alternate dimension. In this dimension, all the rules are different. Deadpool's healing factor doesn't work as well, and Harley Quinn's usual weapons are useless. They have to rely on each other's skills and knowledge to find a way back home. Along the way, they meet strange versions of their friends and enemies, which adds to the hilarity and confusion.
One idea could be that Harley Quinn and Deadpool team up to take on a common enemy in Gotham City. Maybe a new super - villain who has a plan to take over both the criminal underworld and the hero world. They could have a really chaotic and funny dynamic, with Harley's zany antics and Deadpool's fourth - wall - breaking humor.
One idea could be that they both get kidnapped by a mad scientist who wants to study their unique mental states. They then have to team up to escape the scientist's lair.
Maybe Harley Quinn discovers some dark secret about Nightwing's past that she uses to blackmail him into helping her with a heist. But as they work together, they start to understand each other better. Nightwing realizes Harley isn't all bad and Harley sees that Nightwing has his own demons. In the end, they might even become friends or something more.
One idea could be Harley Quinn trying to reform herself and Batman being reluctantly drawn into helping her. Maybe she has some crucial information about a new villain in Gotham and in exchange for her safety and a chance at a new life, she offers to work with Batman.
One idea could be a story where Harley Quinn tries to break free from the Joker's control completely and starts her own life of crime without him. She could form her own gang and prove that she's more than just the Joker's sidekick.
One plot idea could be that Spiderman and Harley Quinn team up to take on a common enemy in Gotham. Maybe a new villain emerges who has technology that can disrupt both of their cities, so they have to combine their skills. Another could be a story where Harley Quinn, being a bit of a wild card, accidentally gets transported to Spiderman's New York and they have to figure out how to get her back while also dealing with the chaos she causes.
One plot idea could be that Harley Quinn is being hunted by a new super - villain in Gotham who wants to use her knowledge of the Joker's operations against him. Batman, despite their past differences, decides to save Harley because he realizes she could be a key in preventing a much larger threat to the city. He manages to rescue her from a dangerous trap set by the new villain and in the process, Harley starts to see Batman in a new light, not just as an enemy but as someone who actually cares about her well - being.