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スタイリストの佐伯奈緒（観月ありさ）は、海外に転勤した姉・美穂の自宅に留守番を兼ねて住んでいた。ある日、奈緒に一本の電話が鳴った。美穂が亡くなったという知らせだった。美穂と夫で奈緒の義兄の望月光彦（椎名桔平）と一人息子の祐輔（広田亮平）がドライブ中に立ち寄ったドライブインで物取り目的の強盗に襲われ、美穂は銃で撃たれ死亡、光彦と祐輔は難を逃れ無事だった。 　　帰国した光彦の頭には包帯が巻かれていた。光彦は美穂の遺骨を抱きつつも、その様子はどこか上の空。実は頭部を撃たれた光彦は、記憶喪失状態になっていた…。Nao Saeki is happy with her life. She has a great job as a stylist, and also has a very sincere and loving fiancé, Kazuya Yuki. But one day, her sister Miho gets caught up in an incident overseas in which she is tragically killed. The shock of Miho's sudden death causes her husband Mitsuhiko to lose his memory. As a result of all that has taken place, Nao has to look after Mitsuhiko and his son Yusuke. At first, Nao is just trying to help the two. But living together and watching Mitsuhiko try to start a new life plants the seeds of a \"new emotion\" within her heart. It doesn't take long for those feelings to turn into love. What Nao doesn't know is that her colleague Chihiro Tomita has feelings for Kazuya, as her own feelings waver back and forth between her brother-in-law and fiancé. When Mitsuhiko's memory comes back, the realization that he has lost his wife is more than he can bear - causing him great anguish. Later, Kazuya finds out about Nao's feelings for Mitsuhiko, and is torn by jealousy. And as the story reaches its final stage, we learn the real reason behind Miho's death.