As the Imperium prepares for the final great battle of the Horus Heresy, all sorts of heroes make the perilous journey to Terra, some to defend the Throneworld and some to cast it down. Among them is Alivia Sureka, a mysterious Perpetual who turned her back on the world long ago. Called back to the planet of her birth, guided by some force she barely understands, and plagued by memories of her long life and premonitions of the horrors to come, she must guide the ship on which she travels safely into the Solar system – for more than just the lives of those on board depend on it…