The Mattigan kids don\'t believe in things that go bump in the night.
To solve this mystery, Maddie, Max, and.
Along the way, they\'ll have to deal with meddling babysitters, suspicious psychics, a YouTube disaster, and their furious father.
But, when their long-lost Grandpa Joe shows up with his Mysterious Monsters journal, begging for help, the siblings find themselves drawn into a search for Bigfoot.
After all, their dad is famous for proving such things are impossible.
The Mattigan kids don\'t believe in things that go bump in the night