On a tiny, wild island in the Gulf of Finland, where the sea meets the sky in an endless horizon, a profound and gentle story unfolds. “The Summer Book” follows the inspirational tale of a wise, irascible grandmother and her fiercely curious young granddaughter, Sophia, as they spend a summer together in rustic isolation. With the girl’s father quietly grieving a recent loss nearby, the island becomes a sanctuary—a world of mossy forests, rocky shores, and limitless imagination where the oldest and youngest members of a family form an unbreakable bond.

This is not a story of grand adventures, but of small, magnificent discoveries. Through a series of vignettes as delicate and interconnected as the island’s ecosystem, the film explores the timeless themes of life, death, nature, and love. It is a lyrical and heartwarming celebration of the wisdom of age and the wonder of youth, a poignant reminder that the simplest moments often hold the deepest truths. The island is their classroom, and their companionship is the lesson.

The Summer Book cast list

1: Emily Matthews as Sophia

Emily Matthews delivers a remarkably natural and insightful performance as Sophia, the young girl navigating the complex emotions of childhood and loss through the lens of a magical summer. Matthews embodies Sophia with a captivating blend of childish curiosity and a startling, preternatural wisdom gained too early. Her performance is a delicate dance of exuberant exploration and quiet contemplation, as she uses the island’s landscape as a playground for both her imagination and her grieving heart.

Matthews’s chemistry with Glenn Close is the beautiful, beating heart of the film. She portrays Sophia not as a passive pupil, but as an equal partner in her grandmother’s unconventional lessons about life. Through her eyes, we see the island’s magic—every insect, tide pool, and storm is a event of monumental importance. Matthews ensures that Sophia’s journey is a deeply moving portrait of resilience, showing how a child’s spirit can heal and grow when nurtured by nature and unconditional love.

2: Glenn Close as Grandmother

The legendary Glenn Close delivers a masterclass in subtlety and grace as the Grandmother, a woman whose stubborn independence and sharp wit are matched only by her deep, abiding love for her granddaughter. Close portrays a woman deeply connected to the rhythms of the island, whose every action, from building a makeshift bridge to identifying a bird call, is a lesson in perseverance and observation. Her performance is beautifully understated, filled with knowing glances, dry humor, and the palpable weight of a life fully lived.

Close reveals the profound vulnerability beneath the Grandmother’s rugged exterior. Her relationship with Sophia is a tender negotiation between teaching her to be brave and acknowledging their mutual fragility. She is teaching Sophia how to live, but also, quietly, how to say goodbye. Close’s performance is a poignant and unforgettable exploration of the unique, fierce, and complicated love between a grandmother and her grandchild, destined to be remembered as one of her finest roles.

3: Anders Danielsen Lie as Father

Anders Danielsen Lie brings a haunting, quiet gravitas to the role of the Father, a man enveloped in a quiet grief who seeks solace in the isolation of the island. Lie’s performance is a study in restrained emotion, portraying a father doing his best to care for his daughter while wrestling with his own profound sadness. He is a peripheral yet constant presence, often seen working on the cabin or gazing out to sea, a figure of quiet strength and unspoken pain.

Lie’s character serves as the emotional anchor to the women’s more whimsical world. His grief is the silent undercurrent of the summer, and his interactions with both Sophia and the Grandmother are filled with a deep, unspoken love and a shared sense of loss. His journey throughout the film is one of gradual re-engagement with life, slowly drawn out of his shell by the resilient spirit of his daughter and the stubborn love of his mother.

4: Ingvar Sigurdsson as Eriksson

Ingvar Sigurdsson appears as Eriksson, a local fisherman or island neighbor who occasionally visits their remote outpost. Sigurdsson brings a wonderful authenticity and earthy presence to the role, representing the few threads that connect the family to the outside world. His character is a man of few words, whose deep understanding of the sea and the weather marks him as a kindred spirit to the Grandmother.

Sigurdsson’s performance, though limited in screen time, adds crucial texture and a sense of place to the film. His visits are events that break the routine, bringing news, supplies, and a different, practical perspective on island life. He is a symbol of the small, interconnected community that exists even in the most remote places, and his respectful dynamic with the family highlights their place within the larger tapestry of the archipelago.

5: Pekka Strang as Mr. Malander

Pekka Strang makes a memorable impact as Mr. Malander, the owner of a neighboring island or a resident from the nearby village. Strang brings a distinct personality to the role, perhaps one of slight exasperation or bemused curiosity towards the grandmother and granddaughter’s unconventional way of living. His interactions with them provide moments of gentle cultural clash and humor, highlighting their unique approach to life.

Strang’s character represents the slightly more conventional world that lies just beyond the borders of their private sanctuary. Whether he is a friendly neighbor or a minor source of irritation, his presence serves to define the boundaries of the family’s chosen isolation and reinforces the special, insular world that Sophia and her grandmother have created for themselves.

6: Sophia Heikkilä as Mrs. Malander

Sophia Heikkilä appears as Mrs. Malander, who likely visits the island with her husband or is encountered in the small village. Heikkilä brings a warmth and pragmatic energy to the role, offering a different feminine perspective from the Grandmother. Her character might represent the traditional expectations of society and motherhood, providing a subtle contrast to the Grandmother’s more free-spirited and philosophical approach to raising Sophia.

Heikkilä’s performance, though brief, helps to flesh out the tiny community surrounding the family. Her presence adds to the rich sense of realism, showing that even in this remote setting, social norms and interactions still exist, and that the grandmother and Sophia’s bond is something extraordinary, even to those who live a similarly rustic life.

Why The Summer Book Is a Must-See

• A Cinematic Sanctuary: A visually stunning and emotionally tranquil film that offers a much-needed escape into the beauty of the natural world.

• Glenn Close’s Triumph: A performance of incredible depth, warmth, and wisdom that is sure to be hailed as a career highlight.

• A Discovery for the Soul: A gentle, philosophical, and life-affirming story that will resonate with audiences of all ages.

• Perfect Harmony: The flawless, generation-spanning chemistry between Glenn Close and newcomer Emily Matthews is nothing short of magical.

The Greatest Adventures Are Measured in Moments. The Summer Book premieres in theaters September 19, 2025.