The repeating Tuesdays are only the beginning...When Japanese high school student Yukari Namikoya finds herself suddenly and inexplicably on another planet, she must quickly come to terms with the fact that she may never see Tokyo again. With a sun that never sets, the desert world of Crimson Winter is on the brink of extinction and day-to-day survival can be difficult; especially for someone used to the modern-day conveniences of Earth.Following the only clue she has to a way home - a cryptic message from a woman long dead - Yukari heads into the desert searching for the Temple of Sapphire. There, she finds the temple in ruins, but what waits there for her is her destiny as a Chosen of the gem god Sapphiros.Stranded on this new world and hunted by the Vile Emperor and his vast forces simply for being what she is, Yukari has no choice but to learn how to fulfill the role she's been cast into and become the long-awaited saviour of a dangerous planet she doesn't yet understand.