The Laughing Ghost — Dorothy Eden

Old Lynnford Carstairs knew his time was running out; knew he had to provide for his headstrong niece, Felicity; knew that only the fear of losing the Carstairs manor house would bring her to her senses. And so he tracked down Lynn Carstairs, son of a distant branch of the family, and left everything to him and Felicity--with the proviso that they marry within the year.

Lynn's arrival at Carstairs couldn't have been more poorly timed for Kiffin Pope, master criminal, for the tortuous tunnels under the house were being used to smuggle a priceless stolen necklace out of England.

That Felicity and Lynn should stumble on the operation was inevitable; but it also seemed inevitable that they, like the ancient actress who was said to haunt the estate, would perish slowly and painfully in the Stygian blackness of the underground caverns....