After the events of Ben 10 X Hoodwinked!: Heroes United, Vilgax arrives at the Galactic Palace in search of the Sailor Crystals and combines them with the powers of the Omnitrix Crystals to resurrect the Sailor Guardian of Destruction and ruler of Shadow Galactica. He manages to bring back the villain, who is also an Emperor of Evil and who was killed in a battle, making an alliance with her and helping her to achieve her new transformation with the Omnitrix Crystals. It's up to the hero Ben 10 and Team Tennyson: Gwendolyn Tennyson and Maxwell Tennyson, to recruit his Happily Ever After Agency friends Little Red Riding Hood Puckett, Granny Puckett, Wolf W. Wolf, Twitchy Squirrel and Verushka Van Vine. The Happily Ever After Agency and the Team Tennyson must join forces to fight and remove these powerful enemies once and for all.