The young Optimis Prime and the Autobots must stop the Decepticons from getting the powerful artifact called the Allspark, an artifact capable of changing all of Earth's machines into an army of Decepticons. Set in the near future Detroit, the Autobots have a new human ally, a girl named Sari, who after an encounter with the Allspark, gains the ability to heal and revive the Transformers.