Miss Strangeworth has lived in this unnamed town all her life.
She was seventy-one, Miss Strangeworth told the tourists, with a pretty little dimple showing by her lip, and she sometimes found herself thinking that the town belonged to her.
This statement is intended to explain why Miss Strangeworth takes the time to greet so many people. From the author's standpoint, this is an easy way for Shirley Jackson to introduce so many of the other characters in the story. Jackson seemed to like using a big cast of characters, as can also be seen in her famous story "The Lottery." It that story she uses a different point of view. It has been classified as: "Anonymous narration--no character point of view" by James Moffett and Kenneth R. McElheny in their excellent book Points of View: An Anthology of Short Stories (Revised Edition, August 1995).
The single character, of course, is Miss Strangeworth. (There is a slight deviation in the scene when she drops one of her letters at the post office and Dave Harris tells his girlfriend Linda Stewart he will deliver it personally to Don Crane the addressee.) Miss Strangeworth is an old maid and lives all by herself, as we see when she writes her poison-pen letters. Most people would describe her as a busybody and a gossip. She wants to know everything that is going on in "her" town. That is why she stops to talk to nearly everyone she meets. Not everybody wants to spend a lot of their time talking to her, but she has considerable status in the town and nobody wants to offend her.
Miss Strangeworth is lonely, a busybody, a trouble-maker, and a self-appointed judge of other people's morals and behavior. She has nothing but time on her hands from morning to night, as we see in the author's description of one of her day's activities. She makes a big project out of going to the grocery store and buying one small, lean veal chop, one box of strawberries, one can of cat food, one tomato, and one quarter-pound bag of tea. This of course will necessitate her coming back again tomorrow and the next day.
Some of the people Miss Strangeworth stops to talk to will be affected by the poison-pen letters she writes that day. She ran into Martha Harper at the grocery store, and she writes her an anonymous letter in which she asks:
Have you found out yet what they were all laughing about after you left the bridge club on Thursday? Or is the wife really the last to know?
She stopped to talk to Helen Crane about her six-month-old daughter and learned that Helen and her husband were both worried about their baby's apparently slow development. She writes another anonymous letter to Don Crane in which she asks:
Didn't you ever see an idiot child before? Some people just shouldn't have children, should they?
Her third letter is addressed to a character who doesn't appear in the story. It exemplifies Miss Strangeworth's technique of asking questions that will plant seeds of doubt, fear, suspicion, and enmity in people's minds. The letter is addressed to an old woman named Mrs. Foster, who ia having an operation next month. The message reads:
You never know about doctors. Remember they're only human and need money like the rest of us. Suppose the knife slipped accidentally. Would Doctor Burns get his fee and a little extra from that nephew of yours?
This letter is her best of the three because it plants seeds of fear and suspicion of both Doctor Burns and Mrs. Foster's nephew in the old woman's mind. Miss Strangeworth has a real talent for her hobby of writing poison-pen letters.