What are the rules? While we sleep, and when we leave the room, the toys are alive. They laugh and play and have lives, but the instant a human enters they must drop where they are like a misplaced toy.
Pixar has a billion-dollar franchise based on that concept, with its four Toy Story movies, related short subjects and merchandise up the ying-yang.
Making up the rules is easy. Making them fly is the real work — and the fun.