The film centers on a young girl, her father, and her grandmother spending a summer on a Finnish island, navigating the recent death of the girl's mother. The narrative focuses on their family dynamics and coping mechanisms. No identifiable LGBTQ+ characters or themes are present in the story.

The Summer Book, 2025, does not include transsexual characters or themes of gender and sexual transformation. The narrative focuses on other aspects, with no elements related to transsexual identity present in the story.

The movie does not contain any action or adventure elements.

The film adaptation of Tove Jansson's novel "The Summer Book" maintains the established genders of its central characters. Sophia, the Father, and the Grandmother are portrayed with the same genders as in the original source material, with no instances of gender changes identified in the adaptation.

The film adapts Tove Jansson's 1972 novel, which features characters implicitly of Nordic descent in the Finnish archipelago. The cast, including Glenn Close, Emily Matthews, and Anders Danielsen Lie, portrays these roles with actors of white European background. This aligns with the established racial context of the source material, indicating no race swap.