Taking its story and setting from the concurrently released TriStar Pictures feature film, Planet 51: The Game is a mission-based driving adventure, set on an alien planet that is oddly familiar. In something of a role-reversal, players take control of Captain Chuck Baker, an astronaut explorer who lands on the strange planet, believing it to be uninhabited. Instead, he finds himself in the midst of picket-fenced suburbs, reminiscent of 1950s America -- except for the "little green men"-like inhabitants, who treat Chuck exactly like the alien invader that he is. The play of the game involves exploring the 3D suburban world from a behind-the-back, third-person perspective, sometimes on foot but usually in a vehicle, and accomplishing tasks such as reaching a distant location or escaping from pursuers. As in the computer-animated movie, the ultimate goal, ostensibly, is to recover Chuck's lost spaceship.

Chuck can commandeer essentially any vehicle he comes across in this travels, including family sedans and motorcycles, taxi cabs and cop cars, and even heavy-duty trucks or zippy riding lawn-mowers. Different cars and trucks have different power and handling, and although the vehicles on Planet 51 hover instead of roll on wheels, most rules of the road still apply. Rules are made to be broken, however, especially when you're a giant alien on the run from a frenzied mob. Chuck can also break from the main story, to interact with various characters from the film in side-quests and various mini-games. In some sequences, players can take control of Lem, the young alien boy who befriends Chuck, and his pet robot Rover, making use of their special skills and abilities to overcome game-world obstacles or beat special challenges. ~ T.J. Deci, All Game Guide