Punchline is the Joker's new right-hand woman.
Alexis was a student of Snyder College who became disillusioned with the world, feeling it was falling apart. After viewing a video of the Joker, she became obsessed with him since she felt he was right and spent a year searching for him. They eventually came into contact through the internet and she tried to prove that she would follow his path wholeheartedly. He taught her how to create a modified form of Joker Venom, which she used to experiment on the homeless community. Following a Joker attack in Gotham City, Snyder College hosted a superhero spirit day, with Alexis dressing with Joker logos. The college's dean Bob went to talk to her, but she exposed him to her Joker Venom, before finally adopting the persona of Punchline and thus successfully proving herself to the Joker.
Road to Joker War
Punchline was hired as a new underboss by The Joker in lieu of his coming war against Batman after Superman revealed his identity to the world as Clark Kent, and Joker decided that a final battle with Batman using his secret identity in play will be fun.
Punchline at first was assigned for a stake-out on Catwoman who had gone to dig a Joker-lookalike corpse, not knowing it was one of his gang member Artie, after The Designer sent a message to Selina. She informed the Joker about her and Harley Quinn having found Artie's body, but he stated it's okay as he had to meet a few people first.
During Lex Luthor's battle against The Batman Who Laughs, Punchline held Mercy Graves hostage while Joker dealt with Lex for using the help of the Dark Multiverse's Batman despite his warnings. Joker however let both go, stating it was a joke all along while Lex got what he needed.
She encountered Catwoman and Harley Quinn while working with Underbroker and fought the latter. Their battle ended with Harley having her neck cut and dumped into a river. She, then, wound Catwoman and used the stolen account numbers to steal the entire Wayne Fortune from Batman.
With Joker in control of the Wayne Fortune and Underbroker in control of Wayne Enterprises, Punchline went in to capture Lucius Fox, poisoning him to take control of Batman's equipment. When Batman returned to the building, Punchline was waiting for him, catching him by surprise with a strange Batsuit black and a crystal blue coloring before mocking him for losing everything and infecting him with a hallucinogenic version of the Joker Serum and driving Batman off
At Tricorner Yards, Punchline and Underbroker doublechecked the arriving shipments of chemicals so they could make a larger batch of her Joker Serum variant before learning of a clown-themed vigilante, Clownhunter, attacking Joker's gang members, but she forced them to get over it. She warned Joker of him and Batman's continued existence, but he was unworried, told her to send some of his more tougher thugs to take care of Clownhunter before going off to kill Harley Quinn.
Finding Harley Quinn and Batman in Eden, a forest area hidden underneath Gotham that Poison Ivy made for Harley, she proceeded to try and torch the place before Harley shot her flamethrower. As they fought, Punchline taunted Harley over thinking she ever thought she could reach the Joker's heart. When Punchline told her own story and how she believed the Joker truly loved her for "understanding" him, Harley lashed out, telling her that he's nothing more than a manipulator and she's just his latest victim, that all he cared about was Batman. Furious, Punchline broke away, ready to kill Batman to prove her point. However, she arrived just as Batman had broken free of her drug thanks to a concoction Harley had given him earlier. Her defeat at Batman's hands was quick.
- Punchline's creator James Tynion IV revealed her last name was "Kaye" in an IGN interview before it was officially confirmed within a series. 
- James Tynion IV has stated that she is intended as an anti-Harley Quinn, being a silent and intimidating serial killer and the fact that the Joker seems to actually care about her.
- 20 Appearances of Alexis Kaye (Prime Earth)
- 23 Images featuring Alexis Kaye (Prime Earth)
- Quotations by or about Alexis Kaye (Prime Earth)
- Character Gallery: Alexis Kaye (Prime Earth)
- The Joker 80th Anniversary 100-Page Super Spectacular #1
- Batman (Volume 3) #98
- Batman (Volume 3) #85-89
- Batman (Volume 3) #89
- Year of the Villain: Hell Arisen #3
- Batman (Volume 3) #92
- Batman (Volume 3) #93
- Batman (Volume 3) #95
- Batman (Volume 3) #97
- Nightwing (Volume 4) #72
- Batman (Volume 3) #93
- Nightwing (Volume 4) #73
- Rich Johnston (February 17, 2020). 'Punchline Should Be The Devil' – James Tynion IV and Jorge Jimenez's Designs on Joker's New Girlfriend. Bleeding Cool. Retrieved on March 26, 2020.