They’re brave, loyal, full of imagination – and now face their most dangerous adventure ever.
Mari is often left to her own devices by her work-obsessed parents, so she spends most of her time with her grandpa Peter and her three best friends. To keep them occupied and quench Mari’s thirst for adventure, grandpa Peter sends the kids on treasure hunts.
Mari and her friends have formed a secret society, and swear to do everything in their power to resolve every adventure that comes their way.
When half the adults in town start acting like children, grandpa Peter realizes what is going on. He gives the kids a secret notebook that has been hidden for over half a century, and which contains clues that will lead them to the cure.
Year of production: 2015
Runtime: 90 minutes