FAREWELL, DANIEL KEYES! According to my notes, this was his last appearance as the caretaker.
Eagle Hill is the happening place tonight! First Barnabas arrives, then is extremely annoyed when he finds that Julia has followed him. She forces him to tell her about the secret room, and now she knows how his father chained him in the coffin. Julia shivers with the cold, but of course it has no effect on Barnabas. She watches very carefully as he opens the secret panel.
Just as Julia is about to tell Barnabas that there's nothing in the secret room, he finds David's broken pocket knife. Julia tries to talk him out of killing David, but he warns her that she might end up her along with-- But he stops himself before mentioning Jason McGuire, whom he killed before Julia entered the story.
He's just decided to kill David when they hear Sam and Dave approaching. Hidden in the secret room, they listen as Sam and Dave finally put it all together: Sarah's grave marker, her clothes, her quaint manner, the brand-new 150-year-old doll. This is more than a coincidence! Dave exclaims. Maybe little Sarah really is a ghost!
By the way, no one ever explains the apparent light source in the secret room or why no one ever seems in danger of suffocating.