If you feel you have lost the purity of your soul by watching stories about rich womanizers seducing impudent women, or by carrying out calculated maneuvers in your own love life, here is a story for you. A boy and a girl from opposite social backgrounds meet and fall in love, a straightforward love which is only possible for a 20-year-old couple.Their love, of course, faces a lot of obstacles.The setting is Yokohama, a modern port city known for its romantic atmosphere. Hiroto Kanzaki (Kazuya Kamenashi) works hard every day and night to fight for the survival of a small ship repair factory inherited from his father, and to support his mother and young brother, who has health problems. Living such an underprivileged life, Hiroto has forgotten how to smile. In contrast to him, Nao Tsukioka (Haruka Ayase) is the daughter of a popular jewelry shop owner on a fashionable street in Yokohama. She was born with a silver spoon in her mouth, literally. Nao attends a prestigious women's college and grew up cheerful, blessed with affluent love. From the moment Hiroto meets her, his closed mind gradually opens up to Nao, who is so innocent that she utters whatever is on her mind. Their three close friends,who are also 20 years of age, play an important role in their developing relationship.

The scriptwriter is Eriko Kitagawa,who earned the nickname 'The Goddess of Love Stories.' This classic love story enables those who are in the same generation to feel empathy, or be envious of the characters' lives; and the rest of us, who were once 20 years old, to reminisce about our own "Love of My Life."

东神奈川县的河边有一间古旧的船只修理工场, 那是神崎　弘人父亲遗留下来的. 父亲死后, 弘人因为要照顾年老的母亲和体弱多病的弟弟, 也为了经营这个工场一直拚命地在这个工场工作. 生活的艰苦令笑容从此在弘人的脸上消失.

某一日, 弘人与好友, 甲（田中圣　饰）和亚裕太（平冈佑太饰）正在把吊回来的鱼拿去卖之际, 在路上与月丘　菜绪及裕子（户田惠梨香饰）, 撞个正. 而菜绪那刚买回来的裙子却被弘人的鱼弄脏了.

同一晚, 弘人, 甲与亚裕太3人偷偷潜进庆应大学与横滨女学馆的party. 弘人因而与菜绪重遇. 弘人因为菜绪打扮随便, 没有其它女生般花枝招展, 因而被她吸引. 可是菜绪却愤慨地对他说她打扮随便只是迫不得已, 因为她本来准备好的裙子被弘人弄脏了. 而理所当然地, 菜绪误会弘人是庆应大学的学生, 而弘人也在完全没有罪恶感地说自己是那里的医科生.

另一方面, 甲与亚裕太也与裕子相遇, 同样地, 他俩也被裕子误为庆应大学的学生. 弘人等3人在身不由己的情况下, 把自己伪装成大学生……

而在party会场的另一角落, 弘人与菜绪双双跌进泳池里全身湿透……