La saison 1 de Tatta Hitotsu no Koi a été diffusée à partir du 14 octobre 2006.

Set in Yokohama, 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.