In the brief golden years of the Edwardian era, Rosie McCosh and her three sisters are growing up in an idyllic household in the countryside south of London. With their neighbors, the two Pitt brothers and the three Pendennis boys, they are "The Pals." But these days of childhood camaraderie and adventure are brought to an abrupt end by the outbreak of World War I, in which some will lose their lives, some their loved ones, some their faith, and all of them their innocence. We follow them through the years of the war--in the trenches, in air battles, in the hospitals where the women serve with as much passion and nearly as much hardship as the men at the front--and its aftermath as the modern world slowly emerges out of the ashes of the old. We come to know intimately this vibrant and eclectic cast of characters, and to see how the connections of their childhood reach deep into their adult lives, the fate of each reverberating in the lives of the others. And at the center is Rosie--in love with one of The Pals and beloved by another--who, in the end, will emerge from tragedy into a profound understanding of what it means to love, not just deeply, but well.