In this historical novel on a grand scale, twin sisters forsake all that is known and familiar to serve on the battlefields of World War I, where their newfound passion leads them to make the ultimate sacrifice. Dorothea and Iris Crosby were born into a life of wealth and privilege. New York City's Park Avenue circa 1915 is a society immune to the turmoil threatening the rest of the world. But for these sisters, identical twins, all of that is about to change. The tragedy of the infamous Triangle Shirtwaist fire, in which hundreds of young women perished, and the news from Europe as the world explodes into war awaken the sisters to the perils around them. As volunteers with the Red Cross, Dorothea and Iris arrive at the battlefront in France, nurses to the wounded and dying young Frenchmen for whom they become les anges, the angels. The terrors of war and the thrill of first love test the bond that holds the two together. But as the losses mount, their union grows ever stronger. Adrift in France at the war's end, they are overwhelmed by memories of their great adventure-- perhaps the greatest they will ever have. Unable to stay, yet unwilling to move on, they find their resolve in the shattering climax to this tale of innocence lost.