The story of the movie is somewhat based on the plot of the most recent game, "Sakura Wars 3," released back in March this year. While the game features Lieutenant Ohgami, the main character who takes off for Paris, narrates one side of the story, the movie unveils the secrets behind Hanagumi. Ohgami leaves for Paris, consequently leaving Hanagumi without a leader; thus a new character will be introduced here. To be replaced with Lieutenant Ohgami is the former leader of Hoshigumi, Rachette Artile - a rationalistic and distinct individual, who brings about serious problems to Hanagumi. The members are now in discord with Rachette. Meanwhile, Teikoku Kagekidan was being threatened by some irrelevant demons and a new type of anti-kouma mechas, (brought by an american company) appears and tries to replace the koubu-kai. Having made repeated mistakes due to the absence of Ohgami, Hanagumi is now faced with an unprecedented danger, while the abolishment of Teikoku Kagekidan Hanagumi is being schemed.
那时，这片土地荒凉，绿草如茵，天空晴朗，空气清新。让我们想象并创造我们自己的幸福家园。一次偶然的机会，他们遇到了一个叫克鲁的中国年轻人，他穿越时空，从古代到现代。凯克鲁出生在一个和平的光明部落，这个部落遭到了一个邪恶残暴的黑暗部落的攻击。克鲁不约而同地遭遇了时空的动荡，来到了现代。7万年前，大雄和他的同伴带着克鲁来到了日本。他们同情这个男孩的困境，决定帮助他打败黑暗氏族，拯救人民
作为《寒蝉鸣泣之时》DVD全9巻购入者特典的“猫杀篇”OVA动画。片头、片尾曲和“寒蝉鸣泣之时”动画（第一期）相同。 前原圭一和其他社团成员玩扑克牌游戏，规则是输家接受惩罚，穿着女仆装、泳装等在村里进行Cosplay游行。
