The story follows a Roman architect named Lucius, who is having trouble coming up with ideas. One day, he discovers a hidden tunnel underneath a spa that leads him to a modern Japanese bath house. Inspired by the innovations found there, he creates his own spa, Roma Thermae, bringing in the modern ideas to his time.
as Lucius
as Mami
as Hadrian
as Ceionius
as Antoninus
as Noboru Itami
as Marukusu
as Shuzo Yamakoshi
as Tateno
as Yumi Yamakoshi
as Kishimoto
as Saburo
as Middle-aged man at bath
as Michiko Hirai
as Ujino
as Showroom department head