Teenage siblings Luke, Celia, and Austin are dreading their summer vacation. A month cooped up in an RV, touring around the Southwest, with their parents, grandmother, and each other? Pure torture.

But when Grandma reveals the real reason for the trip, the journey becomes an unexpected adventure. As they travel through breathtaking canyons, the teens develop new friendships, deepen their faith, and join together to solve a decades-old mystery.

And if the siblings can put down their phones long enough to enjoy the incredible journey, they might just discover that their relationships with each other are truly the greatest treasure.