The 12-year-old boy Leo (Jack Hollington) comes to the home of his classmate Marcus (Samuel Joslin). Here, Leo explains Marcus's warm and beautiful sister Marianne (Joanna Vanderham), who often takes Leo everywhere to play, and Leo likes this amiable older sister very much. By chance, Leo comes to the Black Farm. Here, he meets farmer Ted (Ben Batt). Ted entrusts Leo to bring a letter to Marianne. Leo does. Although he doesn't know what the letter says, Leo finds that whenever Marianne receives a letter, she will show a bright smile from the bottom of her heart. This is the best praise for Leo. Later, Leo meets veteran Hugh (Stephen Campbell Moore) and learns that Marianne's family has decided to marry their daughter to this strong and funny man.