Based on Tove Jansson's beloved novel, The Summer Book tells the story of Sophia, a nine-year-old girl who is growing up fast, and her grandmother, who is nearing the end of her life.
Together with Sophia's father (Anders Danielsen Lie), Sophia (Emily Matthews) and her grandmother (Glenn Close) spend time at their family's summer home on a tiny unspoiled island in the Gulf of Finland, exploring the islet, talking about life, nature and everything but their feelings about Sophia's mother's death and their love for one another.
The course of the summer sees emotional wounds healed, bonds deepened and a peaceful acceptance of what is to come next.