Former idol superstar Seiko Matsuda makes her 2-hour TV drama debut this week in "Tatta Hitotsu no Takaramono (Just One Treasure)" (Nihon TV, Tues., 9 p.m.), which is about the short life of a special boy.

Matsuda plays Yumi, who works for a foreign-owned bank in Tokyo. Through her job she meets Kotaro (Eiichiro Funakoshi) and after a brief courtship they marry. But their dreams of starting a family are constantly foiled by circumstances beyond their control. After many attempts, Yumi finally becomes pregnant and gives birth to a boy.

The boy, however, has Downs Syndrome. The doctor tells Yumi and Kotaro that the baby has many physical problems, including a bad heart, and will probably not live more than a year. The couple raise the boy carefully, and he seems to thrive under their love. They eventually enroll him in a pre-school for disabled children and when he reaches the age of 4, Yumi believes that the miracle will last.