Westminster Abbey is a ghostly place by night. Timbers creak and pigeons and sparrows make fluttering noises high in the clerestory as the watchman makes his rounds.
On Christmas morning, Night Watchman Andrew Hislop, long used to such sounds, came upon a startling sight: there were marks on the carpet indicating that a heavy object had been dragged down the altar steps, through the transept, past the memorial to Dryden and the graves of Robert Browning and Lord Tennyson, to a side door near the Poets' Corner. Hislop rushed to a phone, called the police. "The Stone is gone," he...