The following account is completely true, and, no, there is nothing funny about it.

I was on my laptop in the dining room of my rowhouse in downtown Washington, D.C., when someone rapped at the window. There was a man there, in my backyard. This is a good neighborhood, but a gritty one. Cautiously, I cracked the door.

The man was maskless, but as soon as he saw me, he stepped back a few feet, creating a social distance, a move that seemed friendly. He was in his early 30s, powerfully built. I opened the door fully.

“My name is Seth,” he said. “I’m a neighbor, and I see you walking your big brown dog, and sometimes a cat is with you.” All true. He had established his bona fides. “My mother just died, and she loved cooking green tomatoes.” He nodded toward my small tomato garden. “Could I take a tomato, in her honor?”

He seemed winningly earnest. “You can’t take a tomato,” I said, “but you can take five or six. Just help yourself.”

He looked at me, and then back at the garden. “Can I take a whole plant?” he asked. He sensed my suspicion: It would give him pleasure to watch the tomatoes grow, he explained, cooking them up when they were large and green enough, the way his ma did.

My garden isn’t a garden so much as 17 big plastic pots with a plant in each. There isn’t much dirt in the inner city, so I’d imported my own. His request was a little ... odd, but you know. His ma. I invited him to choose a plant, and he did, and waddled off with it. They’re pretty heavy.

A couple of days later I met him in the street. He was still maskless, but this time was also shirtless. He reminded me who he was and wanted to thank me again for the tomato plants.

Plants?

“I came back at night and took another one.”

Silence. He indignantly asked me to thank him for thanking me for the plants.

“You stole a plant,” I said.

At this point he launched into a high-pitched, high-decibel condemnation of me. It was personal and nasty. He also informed me that he owned five houses and that I should be compassionate and make allowances because his mother had died. I began backing away into my house. He asked me if I had anything to tell him — he really, really wanted that thank you — and I responded that what I most wanted to tell him was to wear a mask.

The next day, there were firetrucks in front of my house. A firefighter told me that there had been an altercation involving a neighbor and a firefighter was injured. The other end of the block was all police cars. One of the cops told me that a man had been selling scrounged goods illegally from a nearby parking lot, and that when he was confronted, he became violent and smashed the window of a firetruck. I looked at the assemblage of scrounged goods. Among the items — a door, some clothes hangers, a broken kids’ bike — there was at least one big plastic flower pot; no plants inside.

The officer said the man was being taken into custody. He nodded toward a police van. From inside I heard someone screaming, “Let me go! My mother died! My mother died!”

Ah.

The next day I stopped at a neighborhood convenience store near where Seth had been apprehended. The proprietor, whom I know well, told me Seth had been a nice man, a good customer, until recently, when he began to act erratically. I asked him if Seth had been released from jail yet. That’s usually what happens with relatively minor crimes.

He looked at me like I was nuts.

“He won’t be released,” he said.

Why?

“He’s been charged with murder. He strangled his mother.”

Email Gene Weingarten at weingarten@washpost.com. Find chats and updates at washingtonpost.com/magazine.

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