Mere happenstance placed Charles Darwin aboard the Beagle, but for the 22 year old scientist, it changed the course of his entire life. Drawing on many sources to tell a colorful tale, the author of Revolutionary Brothers reveals young Darwin in all his complexities: the brashness that came from his privileged background, the Faustian bargain he made with Argentina's dictator Juan Manuel de Rosas, his abhorrence of slavery, his surprising aptitude as a marksman, and an ambition to carve himself a place amongst his era's celebrated travelers and intellectual giants.