Used - Murder With Mirrors

"By and large, I haven't done badly out of marriage," said Ruth Van Rydock. — Jane Marple thought Ruth was putting it mildly. Ruth had been married three times, to extremely wealthy men. Every one of her divorces increased her bank balance without dampening her good humor. — "Of course," said Mrs. Van Rydock, "I've always been tough. I've not expected too much of life - or of men - and I've done very well out of it, and no hard feelings. That's why I want you to visit Carrie Louise - she's always had a tendency to marry cranks!"

So that's how shrewd Jane Marple came to visit Carrie Louise and Stonygates. Two-hundred-odd juvenile delinquents were no problem at all, compared with the half-dozen members of a wealthy family who were intimately connected with murder!