When Bill's two grandsons come for a summer visit, they stumble into a big-time adventure with a giant turtle named Mel. After Bill's neighbor Bailer tries to kidnap Mel in order to feature him in a proposed theme park, the grandsons plot to hide Mel from the neighbor. Then the fun begins, and Mel becomes an unlikely hero!

One magical day, June is running through the woods to find her way home where she discovers an old rollercoaster car and climbs inside. She suddenly finds herself in Wonderland, an amusement park she had created in her mind and put aside. All of her rides and characters are brought to life but are falling into disarray without her. Now, with the help of her fun and lovable park characters, June will have to put the wonder back in Wonderland before...

Two years after a clash of egos forced Mystery, Inc. to close its doors, Scooby-Doo and his crime-solving cohorts are individually summoned to Spooky Island to investigate a series of paranormal incidents at the ultra-hip spring break hot spot. Concerned his park might truly be haunted, the owner tries to reunite those notoriously meddling detectives to sovle the mystery before his supernatural secret scares away the college crowd.