Book excerpt: Eighteen-year-old Bria wants to be a Global Vagabond. In a quest for independence, her neglected art, and no-strings-attached hookups, she signs up for a tour of Central America—the wrong one. Middle-aged tourists are hardly the key to self-rediscovery. So when Bria meets Rowan, devoted backpacker and dive instructor, and his outspoken sister, Starling, she seizes the chance to ditch her group and join them off the beaten path. Bria's a good girl trying to go bad. Rowan's a bad boy trying to stay good. As they travel through Mayan villages and remote Belizean islands, they discover they're both seeking to leave behind the old versions of themselves. The secret to escaping the past, Rowan's found, is to keep moving forward. But Bria realizes she can't run forever. At some point, you have to look back.