A life-affirming story about friendship, adventure and self-belief, from the award-winning author of The Bubble Boy. Perfect for fans of Louis Sachar's Holes and Elle McNicoll's A Kind of Spark.   When three eleven-year-old 'problem children' are thrown together at summer camp, they're challenged to build a place to live together for the next week. But after a trip to a disused tin-mine goes awry, Milo and his new friends, Oscar and Effie, soon find themselves split off from the group and trapped underground. Can they work through their individual issues and come together as a team to find their way to freedom?