The novel which was published in 2015, describes how Shinohara who just transferred to Aoba Kita Senior School, tries to form a band which can perform during the cultural festival. However, the school rules forbids band activities. Despite so, Shinohara manages to form a five-member band including his classmate Moriyama Rin. The performance turns out to be a success but Rin collapses whereby Shinohara first learns of her suffering from a terminal illness. Just before Rin passes away, Shinohara confesses his feelings for her but is rejected by her who reacts violently to the confession. Shinohara realises that he shouldn't have done that and deeply regrets tormenting Rin with his action. 2 months after her death, Shinohara is still plagued by his guilt and accidentally goes back into time at six months ago. This time, he will try to suppress his feelings and allow Rin to leave this world with a smile.
Moriyama Rin who has a terminal illness, falls for a new transfer student Shinohara. When he confesses his feelings to Rin, it is too late as she is on the verge of dying. Out of the blue, he experiences a time leap which offers him a second chance to prevent any regrets.
Filming is expected to begin from 1 October.