"Jessica Rabbit left her oldMadame Inkpersona behind after she cleaned herself up and married Roger, but "Madame Ink" was not going to vanish so easily. Marvin Acme was so smitten with the Madame Ink character that he secretly had a perfect photostatic copy of her image made, and had it stored in his vault... where she slumbered for decades in the darkness. The chance to reintroduce the character in films never came about -- mostly due to a landmark Supreme Court ruling in 1952 that granted citizenship to 'Toons, thus giving them more control over their images. Over the years, Acme begged Jessica Rabbit to allow him to bring Madame Ink out of the shadows, but she always threatened to sue the pants off of him if he ever did so....
...but after so long dreaming in the darkness of the vault, the copy of Madame Ink took on a life of her own, and one night she oozed from her canister and and escaped the studio to begin her own life. Although she was the spitting image of Jessica Rabbit coated in black ink, her personality was that of the villainous and megalomaniacal character that she played onscreen. Having been away from the world for 50 years, she soon learned that there were more cartoon characters than ever... but to her horror, they were all in color -- garish, gaudy, grotesque Technicolor!
Madame Ink felt nauseated wherever she looked. Color was a disgusting fad, a childish distraction from the artistic purity of black and white! Did Fritz Lang use color? Did Ingmar Bergman or Charlie Chaplin use color? No! No true artistic genius EVER would.
At that moment, she vowed to return the world to its natural monochromatic state, no matter what. But... she would need to recruit allies to her cause..."
"Ivy and Harley were returning from a night on the town, and immediately noticed that something was amiss when they ambled into Ivy's subterranean greenhouse lair. There was a sheen of oily black liquid coating the floor, and the surroundings were strangely drained of color.
Madame Ink slithered from the darkness and assessed the two supervillains. "Hmm, not bad, not bad... a real femme fatale type, and her girl Friday! Mmm, yes, I think you two will do quite nicely..."
"Do nicely for what, precisely?" demanded Ivy, furious at the intrusion.
"For my army, dearie. There's a lot of work to be done to get rid of all this COLOR," she said, shuddering at the word, "and you two are just the characters to help me. I can tell we'll be like peas in a pod!"
"Who are you calling a 'character?" Ivy shot back.
"Oh, simmer down, I didn't mean it like that. We're all characters, right?"
Madame Ink was puzzled at the blank looks on their faces.
"Wait one moment... you know, I thought there was something strange about how everyone is acting -- don't tell me -- you two ladies... you don't KNOW that you're cartoon characters? That we're 'toons? Gadzooks! The ignorance in this new age is preposterous, you don't even know what you are!"
Ivy snorted dismissively, but Harley perked up her eyes widened. "Oh yeah!" she chirped, "That's what Mistah J told me one night! I didn't think it was true, but..."
"Wait, what did he tell you?" Ivy asked, suspiciously.
"You know, Red, this whole thing..." Harley waved her arms around, "Gotham, the world, Bats, all of us. Mistah J said none of it makes any sense when you think about. With everything we do, we should be in jail forever, or croaked, but instead we just go 'round and 'round and 'round with no end in sight. He said the only way it works in his head was if we were, you know, made-up people in some kinda story...? He called it, you know, a moment of supersanity, or something..."
Poison Ivy moaned with disgust. What nonsense...
However, during the exchange, Ivy had failed to notice Madame Ink's dark tendrils silently wrapping themselves around her legs... until it was too late. The two villainesses were effortlessly drained of their color, and coated in dark, slick ink.
"Red, she called you?" the Madame cooed, "you're clearly going to need a better name than that..."