Alive and Dead

Martha Crayle trusted everyone, so when the frightened girl arrived at the National Guild for the Welfare of Unmarried Mothers on that drizzly, cold autumn afternoon, Martha gladly took her to the spacious Victorian house where in harder times she had taken in lodgers. But her one remaining boarder, grumpy Mr Syme, was sure the girl was lying. And the very next day, when Martha brought home a saucy girl with lilac lipstick, Mr Syme was positive she was lying too.
Martha still wasn't convinced - until one of the unfortunate girls involved them all in a sinister murder.