On a school skiing trip, Kazuko Yoshiyama talks with her friend Goro Horikawa about her dream boyfriend appearing from the stars.

At school their teacher reminds the class to develop their body and mind, using a folk song that Yoshiyama recognises from her childhood.

After school, Yoshiyama, Horikawa, and Fukamachi are assigned to clean the classrooms; due to someone using the chemicals in the laboratory during spring break they are also told to lock it from now on.

While Horikawa and Fukamachi are disposing of rubbish, Yoshiyama enters the lab and falls unconscious after a beaker smashes, releasing white smoke.

She awakes the following day (19 April) to find Horikawa on the way to school, awakening again upon the imminent danger of roof tiles falling on their heads.

She goes to Fukamachi in the afternoon and tells him what happened, she remembers a childhood incident wherein the two of them were singing the folk song together and playing before a mirror fell and cut both of their hands.

She visualises returning to the laboratory whereupon the teenage Fukamachi explains that he is actually a time-traveller from the year 2660 with the aim of exploring Earth for drugs based on now-extinct plant life.

"[1] He criticized Ryōichi Takayanagi's acting, stating that his delivery "of lines is undoubtedly the result of his brain-waves being controlled by a galaxy inhabited by monotonous no-talents.

The first version was released in April 1983 as the A-side of Tomoyo Harada's third single (7A0275), with a B-side "Zutto Soba ni" also written by Yumi Matsutoya and two different cover pictures, and was included on the original soundtrack album for the film (C28A0279).

[8] The original song was adapted in a commercial for noodles with then-beginning idol Yuki Kudo parodying the 1983 movie shortly after its release.