Using Cybertronian technology acquired from the first series, Cobra builds a gate between Earth & Cybertron. During a skirmish with GI Joe, this gate is damaged, sending members of GI Joe & Cobra to Cybertron. Further feedback causes the gate to make several Transformers disappear. Ultra Magnus & Perceptor erect a force-field to prevent Shockwave & his minions from accessing the gate or harming the humans. The Autobots reveal that the humans must travel into the time stream to retrieve the missing Transformers from Earth or further feedback will cause the reoccurring equivalent of a nuclear holocaust on Earth.