Back to the Farture: Part 1.
Marty Witwicky (Shia Labouef) is sent to the past in the DeBumblebee, a fart-powered time-machine made from a 1976 Chevrolet Camaro by his scientist friend Dr Basil 'Que' Fawlty-Brown (John Cleese). While there, he accidentally alters the past by making his own mother (Megan Fox) fall in love with him instead of his father, after he's hit by a speeding brownie thrown by his maternal grandfather. With the help of the US military, Marty must make his mother fall in love with his father all over again to preserve his own future existence, as well as finding a way to collect enough farts to power the DeBumblebee for his return trip to the far-flung future of 2005.