New Mobotropolis is rocked by the rampaging Enerjak, and even the combined might of Sonic and Shadow may not be enough to withstand his attack! Will this latest onslaught cause Shadow to go too far, and how will the odds change when Eggman throws down into the battle? Also, the tragic origin of the mysterious villain Dr. Finitevus is revealed at last, and it could spell the doom of our hero!