匆忙浮躁的都市中，四个与音乐相关的男男女女看似偶然般地邂逅了，他们分别是第一小提琴手卷真纪（松隆子 饰）、大提琴手世吹雀（满岛光 饰）、中提琴手家森谕高（高桥一生 饰）以及第二提琴手别府司（松田龙平 饰）。仿佛是对音乐的共同志向，他们组建了名为“甜甜圈洞”的四重奏乐队，暂时落脚于别府家位于轻井泽的别墅，过起了与世隔绝的人生。然而四个人终究无法超脱世俗存在，除了最基本的吃饭问题，每个人似乎都被各自的秘密所牵扯纠缠。其中雀与真纪“邂逅”的原因，恰恰正是因为真纪丈夫的不辞而别。 雪花飘落，寒风萧瑟，四重奏的悠扬旋律荡涤且治愈着他们每一个人的心……

On a quiet street in Helsinki, Sachie has opened a diner featuring rice balls. For a month she has no customers. Then, in short order, she has her first customer, meets Midori, a gangly Japanese tourist, and invites her to stay with her.

Eikichi left his hometown in Hiroshima for Tokyo. He tried to find success with his music band, but failed. Several years later, Eikichi goes home to tell his father, Osamu, that his girlfriend is pregnant. His father curses him out, but he is also excited to have a grandchild. Osamu has a party to celebrate the news, but, at the party, he collapses and goes to the hospital. Eikichi struggles to make his father happy.