On each birthday of Andy, it is the same thing, his toys dread the arrival of a newcomer who could supplant them in the heart of the little boy. This year, the worst forecast will come true: Buzz Lightyear, an electronic cosmonaut, makes a triumphant entry. Disrupting the order of things, he quickly becomes the hero of Andy and the other toys. Destroyed and dishonored, Woody the cowboy is therefore ready to do anything to regain his first place in Andy's heart and his status as head of toys ...