Berry is a girl living in the data-managed city of Tom Sawyer Island. Her hobby at the moment is trying to catch Phantom Zero, who's believed to be behind the cases of Love loss known as the Zero Phenomenon. One day, when she heads into town to get the broken Deco in one of her eyes fixed, Berry runs into a kid who seems like a ghost, due to being unable to be seen with Deco. Suspecting she may have finally found the Phantom, Berry begins her chase.

Berry and Hack are somehow able to escape from the Hyperverse that Phantom Zero pulled them into. But before long, Hack is apprehended by the customer center, who are investigating the Zero Phenomenon. The next day, Berry wakes up on the veranda of her apartment, and after trying to explain what happened, her friends point out to her that there is no evidence of Zero Phenomenon having occurred, much less of the kid she encountered. Not taking no for an answer, Berry decides to dig up proof behind the Zero Phenomenon.

After being suspected of being Phantom Zero, Berry and the club use Deco disguises in order to escape. Meanwhile, the customer center is in a frenzy, thanks to reports of Phantom Zero that they're receiving from all over the place. They dispatch a search team to the slums. Finn and the detective club take shelter in one of Finn's secret hideouts, with Finn stating the only way they can clear their names is to head to the mysterious location known as Mark Twain, and apprehend the true Phantom Zero.

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.

A young girl awakens in a empty white space. She's enjoying a happy life with her parents, staring out at her pet peacock. But then, from out of nowhere, Berry appears. The girl is surprised, and attempts to run away.