The motherless oven

Like Jan Svankmajer doing Grange Hill, this sets up a bizarre but kind of recognisable world that has its own internal logic and very little in the way of explanation. Scarper Lee is a schoolboy doing normal schoolboy things in a place where your dad might be a steam-powered boat on wheels and it rains knives on a regular basis. He's got three weeks to live and he knows this because everyone knows when their deathday is. Then things start to change when he meets new girl and agent of chaos Vera Pike. It's hard to explain where things go from here because it only makes sense if you read it (and you have to read all three books in the trilogy to get anything like a complete story), but the worldbuilding and character development are top notch.