HURRICANE HEROES, TONIGHT ON ABC'S "20/20"

What does it take to come to a complete stranger's aid when your own life is hanging in the balance? Elizabeth Vargas anchors an hour on heroes, including some of the amazing stories from Hurricane Sandy, tonight on ABC's "20/20" (10:01-11:00 p.m., ET). The hour will also give viewers the latest information on the aftermath the Hurricane Sandy.

Plus: Private Channing Moss was on patrol in Afghanistan with members of his platoon from the 10th Mountain Division from Ft. Drum, NY when he was struck by an RPG that lodged in his lower abdomen -- but didn't explode. The soldiers' rulebook dictates, in this rare incident, that the wounded soldier should be moved aside and made as comfortable as possible, but that the lives of others should not be risked to save his. A series of tough calls - all against the rules - then ensued. Elizabeth Vargas has the heroic story of Saving Private Moss. (OAD: 5/27/11)

Also: When a hideous car crash occurs on a highway, why do some people rush in to help while others stand by, even snapping ghoulish photos on their smartphones? A team of noted psychologists hope to crack the code of bravery and teach us all how to unlock the superhero within. Jim Avila reports. (OAD: 9/7/12)

David Sloan is executive producer of "20/20".