Sherlock Holmes (1984)

S1E4 The Solitary Cyclist

Violet Smith, a new music teacher for Robert Carruthers, resides at his country home during the week. Concerned about a mysterious cyclist who shadows her weekly on her trips to the train station, she seeks Holmes' help. Meanwhile, Carruthers proposes to Violet, but Holmes uncovers a troubling link between him and her relentless pursuer, suggesting that not everything is as it seems in this idyllic setting.