Zoe's dad isn't home. She still sees him in photographs, laughing and playing tennis, but for now she can only visit him in a building where everyone looks sad and the walls are an ugly pink color. Some days Zoe's dad is too sad to see her, but she goes to the hospital anyway. While waiting she meets Sabina who invites her to swim across the world. Zoe's not sure it's possible, but Sabina tells her, "A girl can do everything she wants." Even though Sabina sometimes dives deep into her own thoughts, the two of them swim around the world many times that summer, until eventually Zoe's dad is ready to come home.

The Summer of Diving is a book full of imagination and hope with a tender child's-eye understanding of the world. Stridsberg's story and Lundberg's lush and colorful paintings reflect and validate a child's feelings of loss and longing for closeness when a parent's joy for living temporarily fades.