At the end of the 18th century in the village of Lamberley a young girl, Janet Burrows, is found with blood pouring from a gaping neck wound. With her dying screams ringing in their ears, the villagers turn on the local aristocrat Lord St. Clair and burn him and his mansion to the ground. More than a hundred years later, a tall figure drops a rose on Janet Burrows' grave. His name is John Stockton (Roy Marsden), a descendant of the murdered Lord. That night Stockton dines with another new arrival to the village, Bob Ferguson (Keith Barron). Ferguson has been busy arranging the baptism of his baby son but this is destined never to take place. Tragedy strikes the morning after the dinner - Ferguson's son is found dead. Four days later Lamberley's vicar is recounting this story to Holmes and relaying his suspicions about Stockton's connection to these strange events. However, he neglects to tell them that the St. Clair family were thought to be vampires! Is there a rational explanation for these strange happenings? Or is the village priest just a muddled old man in need of reassurance? Only a visit from Holmes (Jeremy Brett) and Watson (Edward Hardwicke) will uncover the truth.