NHK has announced more cast details for its 2010 taiga drama "Ryomaden." Based on the life of the Edo-era figure Sakamoto Ryoma, the show was first revealed last year with actor/singer Masaharu Fukuyama starring as Sakamoto. Now it is known that actress Ryoko Hirosue will play the heroine as his first love.

Hirosue had a one-episode appearance in NHK's 2003 series "Musashi," but she has never had a recurring role in a taiga drama before.　Her character, Hirai Kao, was the sister of Sakamoto's friend, Hirai Shujiro.

The rest of the supporting cast includes Teruyuki Kagawa as Iwasaki Yataro, Tetsuya Takeda as Katsu Kaishu, and Katsumi Takahashi as Saigo Takamori. The series starts airing in January 2010.