Vega, 9, and her wild sister Billie, 5, are going on an overnight outdoor hike in the lush Norwegian woods. The trip is full of exciting climbs, silly jokes, and happy trekking until Dad pulls one acrobatic stunt too many, falling into a cave and injuring his leg badly. Unable to move, he asks Vega and Billie to get help. Anxiously retracing their steps, they know that everything depends on them now, as Vega tries to keep them focused on the goal despite setbacks, surprises, and Billie’s many distractions. They bravely face their fears, discover their superpowers, and find strength in their sisterhood.