France, 1918. Nurse Marcelle Marchand's role as a spy has put her in danger from the German army. American soldier George Mountcastle feels an instant connection to the young nurse. Soon, George and his best friend Philip are fighting for their lives during the Second Battle of the Marne. On the run from a victorious Germany, George and Marcelle begin a new life with Philip and Marcelle's twin sister, Rosalie, in occupied France. Years pass, and tragedy strikes, sending George on a course that could change the past. Playing with time is a tricky thing. If he chooses to alter history, he will surely change his own future - and perhaps not for the better.