With the Decepticons completing their Space Bridge to Cybertron, Optimus Prime and the Autobots race to stop Megatron from opening the Bridge and bringing forth a vast army of Dark Energon zombies from the Transformers' dead home planet.

While on a scouting mission in theArctic, Bulkhead and Bumblebee find a crashed space pod buried in the ice. They bring it back to base for examination, and Optimus Prime and Arcee venture out into the Arctic to find clues on the pod's origin. While they are out, the other Autobots discover that the pod contains a large swarm ofScraplets, a vicious and highly dangerous form of Cybertronian wildlife that eats metal. The Scraplets infest the Autobot base, devouring any metal in sight and damaging the Ground Bridge, leaving Optimus and Arcee stranded in the Arctic.