In which Sherlock Holmes arrives at Baskerville Hall and, after a careful supper and examination of ancestral portraits, begins to weave the strands of the mysterious case more tightly around the elusive Stapleton, revealing unexpected connections and setting a plan into motion. Holmes and Watson then depart for London to pursue urgent inquiries, leaving Sir Henry to navigate the moor alone, while a crucial visit to Mrs. Laura Lyons uncovers fresh revelations that bring the investigation into sharper focus.