In 2014, the 27-year-old son of adventurer Roman Dial walked alone into the Costa Rican wilderness. "I'm planning on doing 4 days in the jungle," he wrote in an email before leaving. "It should be difficult to get lost forever." Then he vanished. Dial talks about his frantic search for his son — and for answers to what happened. His book is 'The Adventurer's Son.' Maureen Corrigan reviews 'Scratched,' Elizabeth Tallent's new memoir about perfectionism.