In the summer of 1900, a young boy named Leo becomes the unwitting messenger in the passionate secret romance between two people from different social classes in an elegant English estate. Twelve-year-old Leo is sent to spend his vacation with his charming yet somewhat distant wealthy friend Clive at his family's grand house. The tranquility of summer is soon interrupted when Leo learns that Clive is in love with a beautiful and promising young woman, the sophisticated and intriguing Marian.
With little Leo as the intermediary, love blossoms in secret as he carries letters back and forth, becoming the bearer of a secret that transports him into a world of emotions and complications. However, as social tensions and the reality of class differences begin to emerge, the innocent game of messaging spirals into a whirlwind where passions can have devastating consequences.
Young Leo, caught between the innocence of his age and the maturity required by the game of love and desire, is forced to confront the effects of his actions. As the different realities collide, the summer transforms into a mixture of disillusionment, loss, and the end of childhood, leaving Leo forever changed by the experiences of that pivotal summer. With cinematography that captures the elegance and tension of the era, this story is a nostalgic journey that explores the ravages of love and the inevitability of growth.