When nurse Ibuki visits the home of a boy who was brought to the infectious disease ward by mistake, she sees a horrifying scene there.

Tomoko Tamura, a second-year high school student living in a detached house in Miyahara-chō, Omiya City, Saitama Prefecture (now Kita Ward, Saitama City), goes on an overnight hot spring trip to Izu with eight of her classmates, four boys and four girls, to enjoy her last summer before their entrance exams. However, Tomoko cleverly gets off at a station along the way to buy some ekiben (boxed lunches), which causes her to miss the train and get separated from her friends. From there, a series of tragedies unfolds in this coming-of-age comedy. Based on the comic by Minako Fujino. Screening alongside the film is That's Cheating! The Biggest Plan in History? (starring Tatsuya Yamaguchi and Namie Amuro, directed by Hiroshi Sugawara) as a double feature theatrical release.