In a dystopian future after a cataclysmic event nearly destroyed the world, Eggman Industries has practically taken over, under the disguise of a helpful charity organization. However, their leader, Dr. Robotnik, is really funding a secret search for the Chaos Emeralds, which have been scattered across the world after the previously mentioned event.
Out of the nuclear fallout, an island was formed. Mutated animals were born and raised for the past two decades, and they have only survived through the power of a sacred artifact called the Chaos Shard, which keeps the island alive. One day, a citizen of the island, Sonic the super-fast mutant hedgehog and his partner Tails the super-smart mutant fox discovered a factory. The humans had discovered the island and have begun building bases.
At a conference in New Washington, Robotnik reveals that they have found readings of Chaos Energy on a far island, and that Chaos Energy is a powerful substance for good, depending on how you use it. He tells them it can heal Earth's resources and help the humans come together for an age of peace.