19-year-old Hinako Mukaimizu moves to an oceanside town to attend college and go surfing, without future thoughts.

When a fireworks display sets her apartment building ablaze, she is rescued by Minato Hinageshi, a 21-year-old firefighter with a strong sense of justice.

However, Minato is reminded of his mortality, after realizing he cannot physically touch Hinako and when his co-worker, Wasabi, confesses to her.

Hinako learns she was the one who saved Minato from drowning when they were young, and when she unlocks his phone, she reads his drafted text message telling her to "ride her own wave."

At her part-time job, Yōko overhears the same group that set off the previous fireworks planning to do so again at the abandoned building housing a large Christmas tree.

After exchanging final farewells with Yōko, Wasabi and Hinako, Minato's spirit ascends to heaven.

[5] He described it as a "simple romantic comedy" that will have "a lot of exciting scenes", including some depicting the contrast between water and fire.

[7] A music video animated by Science Saru, featuring the members and new original scenes from the film, released on June 21, 2019.

[8] To promote the film, a two-chapter manga adaptation by Machi Kiachi was serialized in Deluxe BetsuComi, which contains an original story about Hinako and Minato.

[22] The film became one of the Jury Recommended Works in the Animation category at the 23rd Japan Media Arts Festival in 2020.