1786, Jerusalem College Cambridge. The ghost of Sylvia Whichcote is rumoured to be haunting Jerusalem since disturbed fellow-commoner, Frank Oldershaw, claims to have seen the dead woman prowling the grounds. Desperate to salvage her son's reputation, Lady Anne Oldershaw employs John Holdsworth, author of The Anatomy of Ghosts - a stinging account of why ghosts are mere delusion - to investigate. But his arrival in Cambridge disrupts an uneasy status quo as he glimpses a world of privilege and abuse, where the sinister Holy Ghost Club governs life at Jerusalem more effectively than the Master, Dr Carbury, ever could. And when Holdsworth finds himself haunted - not only by the ghost of his dead wife, Maria, but also Elinor, the very-much-alive Master's wife - his fate is sealed. He must find Sylvia's murderer or the hauntings will continue. And not one of them will leave the claustrophobic confines of Jerusalem unchanged.