When she opened the door, I was disconcerted: Geraldine Graham looked so much like her son that I could almost believe it was Darraugh in the doorway dressed in rose silk. She had his long face and prominent nose and eyes of the same frosty blue, although hers were clouded now with age. The only real difference was her hair: over the years Darraugh’s blond has bleached to white; hers was dark, a white-streaked nut-brown that owed nothing to a bottle. She held herself as ramrod straight as her son. I pictured her mother tying her to a Victorian backboard which she then passed on to Darraugh.

It was only when Geraldine Graham moved away from the doorway and the light caught her face that I saw how deeply lined it was. “You’re the young woman my son sent out to see who is breaking into Larchmont Hall, eh?” She had the high fluting voice of deep age. “I wondered whether that policeman was going to arrest you, but you seemed to talk your way out of it. What made him arrive?”

“You were watching me, ma’am?”

“The hobbies of the elderly. Peeping through windows, prying into locks. Although I suppose my hobby is your livelihood. I’m making a cup of tea. I can offer you one. Or I have bourbon: I know detectives are used to stronger beverages than tea.”

I laughed. “That’s only Philip Marlowe. We modern detectives can’t drink in the middle of the day: it puts us to sleep.”

She moved down the short hallway to her kitchen. I followed and felt a stab of envy when I saw the double-door refrigerator and the porcelain cooktop. My own kitchen was last remodeled two tenants back. I wondered what it would cost to install an island cooktop like this one, with sleek electrical burners that looked painted into the surface. Probably two years of mortgage payments.

Ms. Graham saw me staring and said, “Those are designed to keep the old from burning down the house. They turn off automatically if there’s no pan on them, or after some minutes if you haven’t set a special timer. Although we’re told the old should burn and rave at the end of day.”

When she slowly pushed a small stepladder into position to reach her tea bags, I moved forward to help. She waved me off with a brusqueness like her son’s.

“Just because I’m old and slow doesn’t mean the young and swift need muscle me away. My son keeps wanting to install a housekeeper here so I can vegetate in front of the television or behind my binoculars. As you can see, we’d be tripping over each other all day in this tiny space. I was glad to give up all that nonsense when I moved out of the big house. Housekeepers, gardeners, you can’t take a step without consulting someone else’s feelings and timetables. One of my old maids comes every day to tidy and prepare meals-and to make sure I haven’t died in the night. That’s enough intrusion.”