High school senior Heita Fukai (Takeru Sato) doesn’t know what to do with his life.  Having been seriously ill until recently, he never had the opportunity to think about his future.  He leads a mundane existence among his classmates, all of whom are struggling with their own issues.  There’s the popular guy with secret hang-ups, the boy who can’t afford the tuition, the girl with bulimia and the pathologically shy kid.  The teachers don’t fare much better.  The high school is a microcosm of our troubled modern society.

One day Fukai stumbles across a mysterious and attractive new girl in school, Q10 (Atsuko Maeda), whom he soon finds out is actually a robot.  Assigned by the principal to be her mentor and told to keep her true identity a secret, Fukai tries to teach Q10 about human feelings.  In the process, he becomes aware of his own complex, emotional makeup.  Fukai realizes that he is learning about life from an android, and that he may be falling in love with her.

私立高中3年级的平太（佐藤健饰） 某一天在无人的理科实验室发现了坐在窗边的神秘女孩。一动不动的女孩的脚底刻有「Q10」的文字。平太一个不经意的触碰竟然唤醒了那个女孩！“启动后，请在10秒以内取名”。平太不知所措，情急之下取了脚底的文字「Q10（CUTE）」为名字。从那时起，Q10就开始缠着平太，无论何时都喜欢围着他转。

校长岸本（小野武彦饰）和教师小川（田中裕二饰）以及对Q10感兴趣的理工学博士柳（药师丸博子饰）为防止事态扩大，决定保守Q10是机器人的秘密，让其隐藏在学校。

像刚出生的婴儿一样单纯的Q10慢慢地影响着每天了无生趣地生活的平太以及班级的同学们。

有一天，Q10和平太目击了用刀子撕开校长椅子的学生…。