"If I could have any superpower," says Samantha Appleton, "I would want to be invisible." For Appleton, a 32-year-old photojournalist who has covered the war in Iraq off and on, this is not just an idle wish—it's a professional necessity. And in this, she has a distinct advantage over her male colleagues. When Appleton wants to disappear into the crowd, she dons an abaya, the long, black garment worn by women in Muslim countries. Most men ignore her; in conservative areas, they won't even make eye contact with her—a dream come true for a documentary photographer.

Though she's been at it for only seven years, Appleton's lush, visceral style has won her commissions from Time, The New Yorker, and The New York Times. She got her start in 2000 as an assistant to the acclaimed war photographer James Nachtwey, who cites her bravery in making "powerful, resonant photographs of issues that need to be in the public eye." But she soon began to generate her own stories, traveling alone to global hot spots, usually without a set assignment. Her big break came in April 2003, when she drove from Amman, Jordan, into Iraq just after the fall of Baghdad. At that point, most foreign journalists were exhausted and heading home, which left Appleton with a windfall of plum assignments that might otherwise have gone to more experienced photographers.

The pictures she shot that spring—and on five subsequent trips to Iraq—capture the brutality and chaos of war in swarming, off-kilter compositions packed with humanizing details. Although she's interested above all in documenting the effect of war on civilians, Appleton has also been embedded with U.S. military units. On these missions, there's tons of downtime. "Then all of a sudden," she says, "you're out on a patrol and you spend 20 minutes terrified out of your mind."