Nia has been making herself at home in Tidmouth Sheds, but Gordon isn't content with the new changes, even more so when Henry reveals that he is leaving Tidmouth Sheds. Angered and saddened by this, Gordon goes on tantrum, until Nia convinces him that the changes might not be so bad, especially when another new engine arrives and takes Henry's berth.

Cherry, Atticus, and Mo bring Lionel to Mr. Litwak's Arcade which they haven't visited in quite sometime, and of course, get sucked into a brand new adventure with their old friends: Wreck-it-Ralph and Vanellope von Schweetz. Sugar Rush is in danger of being unplugged because of an accident, and they must travel to the internet to save the future of the racing game.

When the gang meets up with famous fright-writer Ben Ravencroft, he invites them to New England for his hometown's Autumn Harvest Festival. But things take a turn when a man anmed Lucifer comes out fo nowhere and plots to take revenge by summoning the dreaded Chronos the Grim Reaper! Now, the gang is on the case as even the monsters, Ghoul School kids, and Boo Brothers appear.