Inako Natsui is a quiet, modern girl working in a laboratory and living a closed and somewhat monotonous life in a small town. From time to time she goes to nearby to visit her lonely mother Wakayama who has been a widow for the past seventeen years. The girl's relatives, particularly Aunt Sadako and Uncle Shuhei, the local mayor's deputy, plan to introduce her to a suitable young man, but Inako has no real desire to get married. She is more interested in the hot mineral springs from where she takes her laboratory specimens. This all changes when she meets Mr Tamamiza, a young divorced man who's been left with a little boy. Her relatives are decidedly against the match. The girl falls in love with the man without realizing that she will encounter a painful conflict between her family and providence, as unexpectedly as the spring which gushes out from the geological fold, driven to the surface by mysterious subterranean forces.