Mud, barbed wire, the smell of death... The year is 1917 and the TARDIS has materialised on the Western Front during the First World War. Or has it? For very soon the Doctor finds himself pursued by the soldiers of Ancient Rome; and then he and his companions are reliving the American Civil War of 1863. And is this really Earth, or just a mock-up created by the War Lords?
As Doctor Who solves the mystery, he has to admit he is faced with an evil of such magnitude that he cannot combat it on h...