Thanks to Doron and his drone friends, Berry, Hack, and Finn are able to reach Mark Twain, a strange facility floating in the sky. By using the Angelfish club card they had previously obtained, they manage to get inside, where Berry and Hack enter Mark Twain's rendition of the Hyperverse. What they discover appears to be a labyrinth. Knowing that all the secrets of Tom Sawyer island must be contained within, Berry and Hack start searching for Phantom Zero's identity.