Episode Description : Optimus Prime loses all memory of being a Prime after using the Matrix of Leadership to send Unicron back into stasis. Megatron takes advantage of this and takes "Orion"(Optimus's name before becoming a Prime) on to the Nemesis, convincing him the Decepticons are good and the Autobots are evil (Before becoming a Prime, Optimus and Megatron were close friends). The Autobots are distraught at this turn of events, and upon discovering that Jack has the Key to Vector Sigma (an ancient super-computer containing infinite knowledge), they devise a plan to get their leader back.