It was the last-chance moment of the war. In January 2007, President George W. Bush announced a new strategy for Iraq. It became known as "the surge." Among those called to carry it out were the young, optimistic army infantry soldiers of the 2-16, the battalion nicknamed the Rangers. About to head to a vicious area of Baghdad, they decided the difference would be them. Fifteen months later, the soldiers returned home -- forever changed. The chronicle of their tour is gripping, devastating, and deeply illuminating for anyone with an interest in human conflict.