Not to be confused with the rather more famous Edinburgh Castle in Scotland - this "Edinburgh Castle" is more of a stone manor house. The building has a castle-like appearance, with its two circular towers, useful for shooting at enemies - or, if you were the owner - random travellers who happened by.
Lewis Hutchinson was a doctor from Scotland who bought the land here in 1768. By 1770, he'd earned the nicknames "The Mad Master" and "The Mad Doctor". See if you can spot the word that links those two nicknames. Nobody local went near Edinburgh Castle if they could help it. But the main road in the area went right by the manor house, meaning many travellers walked directly into Hutchinson's path.
Hutchinson would shoot his victims from one of the towers, take their valuables, and have his slaves toss the body into a nearby sinkhole. If someone happened to stop and ask for hospitality, he would invite them in ... and they would never leave.
Hutchinson was arrested in 1773 for murder, and subsequently hanged. Nobody knows how many people he killed in his 5 years at the castle, but after his execution, a collection of 43 watches was found inside.
So at least 43, I'd say.