Frank Harris is hit by a ray that sucks him into Cool World, the cartoon created by Jack Deebs (Byrne) about 50 years later. Meanwhile Cool World's bimbo Holli Would (a cartoon Basinger) drags the artist into his sketches because making "the beast with two backs" with a human will turn her into one.
Harris, now the comic strip's flesh 'n' blood policeman, has to stop them, as this would disrupt the universe. He doesn't, it does, but a cartoon Deebs stops life as we know it turning into a drawing. Confused? Well, Cool World is that sort of film. Half animation, half live action; plot progression unencumbered by logic or logistics; as much going on in each frame as possible, but not a great deal actually happening.
It's a movie hoping to get by on attitude alone, and while such a reefer-happy state of affairs worked for Bakshi in Fritz The Cat and Heavy Traffic, years later expectations and popular drugs have moved on. Regardless of how daring and dangerous Cool World thinks it is being, all it actually does is sacrifice everything that makes a feature film bearable for the sake of one protracted joke (humans interacting with cartoons behaving to type), "clever" effects (it's all been done before, and better) and glimpses of Kim Basinger's knickers.
Apart from Byrne and Pitt doing their best in an irredeemable situation and interestingly dense animation landscapes, Cool World has nothing to recommend it. Hopeless.