As a computer virus based on Pac-Man invades Japan, a group of doctors attack Genm Corp and begin a wave of terror using stolen Proto Gashats. Ghost and Ex-Aid find themselves at the center of the fight in an effort to protect those most important to them. But they aren’t alone, as Heisei Riders from the past join them to stop Dr. Pac-Man!

As Pacworlders excitedly decorate for Berry Day, Pac is saddened about missing his parents as he receives a picture ornament of them from his Aunt Spheria. The teens reminisce of their childhood Berry Day as they enjoy Christmas eggnog. Since Berry Day is one of the happiest days of the year, Betrayus launches a plan to get rid of the day by capturing Santa Pac and his Round Deer and to possess the gifts and Berry Day decorations. All Pac wants for Berry Day is to see his parents Sunny and Zac and is overjoyed when they arrive. But, his parents tell him they want to see the tree of life in the secret location which is forbidden. Are these Pac’s real parents or are they a trick from Betrayus and Dr. Slimestein? Let’s hope Berry Day can be merry after all.