Set in a world where superheroes are commonly known and accepted, young Will Stronghold, the son of the Commander and Jetstream, tries to find a balance between being a normal teenager and an extraordinary being.
Scooby-Doo and the gang are on the case when a mysterious lake monster starts scaring the guests at a summer resort in Erie Point, where Fred, Daphne, Velma and Shaggy have taken on seasonal jobs to pay for a barn they accidentally burned down. But in addition to sneaking suspicions, there's some romance in the air.
Alone on a tiny deserted island, Hank has given up all hope of ever making it home again. But one day everything changes when a dead body washes ashore, and he soon realizes it may be his last opportunity to escape certain death. Armed with his new “friend” and an unusual bag of tricks, the duo go on an epic adventure to bring Hank back to the woman of his dreams.
During a championship baseball match, the three brothers hear that their grandfather in Japan is in trouble, and head out to help him, conceding the match. When they arrive in Japan, they must use all their powers to defend him against his ancient enemy, who has returned to exact revenge.