We get called to a minor injury in Marine Park, late on a freezing cold Thursday night. The house is a brick-and-stone Tudor on a huge lot, with a flagstone patio overlooking a yard landscaped with evergreens and bare fruit trees – a Brooklyn beauty easily worth $750,000.

An emaciated 35-year-old woman with a twitching eye greets us at the front door and tells us to come through to the back. She’s pale, with hollow cheeks, and is clearly agitated. A child of about 6 sits on the sofa watching cartoons even though it’s past 11 p.m., his hand in a bag of microwave popcorn.

The woman is all over the place, jumping ahead of us, behind us, to the side of us, telling her story. “This guy came to fix my car, see? And he fell. See? And I think he broke his leg. Okay?”

Car repair at 11 p.m. on a Thursday night? We step over children’s toys and strewn laundry and open the sliding patio door. The wooden stair leading to the patio is splintered, and a young Hispanic man of about 20 is lying on the flagstones clutching his lower leg. He’s dressed in slouchy clothes and has gold-capped teeth, which flash in the porch light as he grimaces in pain.

It doesn’t take a detective to figure out that he’s a drug dealer, and that this housewife is most likely a customer. He fell, and now red lights are flashing and the entire neighborhood knows about this undesirable visitor who “came to fix the car.” The woman wants the whole thing over with as quietly as possible. The dealer is clearly angry with her for calling 911, but his foot is flopping like a fish, his left lower tibia snapped and bulging just under the skin, and he knows he has to go to the hospital. He’s hoping we’ll get him out of there before the police show up. “Yo, just get me to the hospital, okay?” he says. We take him around front to the ambulance, splint his leg – I take my time, hoping the police will show up – and then get ready to transport. As we pull away, I notice a FOR SALE BY OWNER sign hanging on the front gate.

The next day, I drive by the house. It’s even more lovely in daylight, and I take down the owner’s telephone number. I drive a block away, park my car, and take out my cell phone.

All I want to know is how much she’s asking, but an older woman’s voice answers the phone.

“Hello,” I say. “I was, um, driving by and noticed the for sale sign on your house. How much are you asking?”

“$775,000,” she says. Then quickly adds, “But we’re negotiable. We’re eager to sell.” After a brief pause in which neither of us speaks, she says, “Do you want to look at it?”

It was dark, I think. The housewife was strung out. She probably wouldn’t recognize me out of uniform. “Okay,” I say. “What time is good for you?”

“I live a few blocks away. I can be there in 15 minutes,” she says.

I park in front of the house to wait, and have another look at the yard. A plaster Madonna in a blue clamshell, some Christmas-decorated evergreens, a beautiful front door. Fifteen minutes later, a car pulls up, and a well-dressed woman of about 60 comes out and shakes my hand. She introduces herself as the owner, tells me the basics about the house, the year it was built, the renovations, and then leans in closer. “My son and his wife are having trouble.” She lowers her voice. “She’s an alcoholic. He moved back in with me and my husband. They’re divorcing and he’s trying to get custody.”

My first reaction is to tell her what I know. But the woman is already taking me by the hand, showing me around the first floor. The varnished inlaid parquet floors squeak under the soles of my boots. She points out the handiwork her son did: new spindle banister, brand new kitchen, new sliding glass patio door. She opens it, and explains the broken stair. “My grandson broke it the other day, playing. It’s easy enough to fix.”

I bite my tongue, but I’m thinking that I want to cut her a deal: I’ll give her the info that’ll get her son custody of the kid if she cuts the price down to $650,000.

She shows me the upstairs: three bedrooms (one of the doors closed), a huge bath with a new marble Jacuzzi tub and heated tile floors, and an iron spiral staircase leading to a finished attic with dormer windows. She rubs a hand along a windowsill. “He’s a carpenter by trade, all his work is solid.”

I worry the emaciated woman is going to pop out of the closed bedroom, point a finger at me, and blow my cover.

“My daughter-in-law sleeps until the afternoon,” the woman whispers. “She’s not involved in the selling.”

I head down the varnished stairs and ask to see the yard, and together we walk along a stone pathway. I imagine the fruit trees in blossom.

“It’s a double-lot, is why it’s so big,” she says.

It’s all the privacy I’d ever need. I’m practically salivating.

I stop. Maybe for $550,000? Surely her grandson is worth $200,000.

Stop it, I think to myself. Just stop it right now.

I sigh and thank the woman for letting me see the house. I tell her I’ll call with an offer, say goodbye to the beautiful fruit trees, and take my leave.

Ms. Klopsis is an emergency medical technician for the FDNY. This column details her observations and experiences on the job. Some names and identifying details have been changed to protect the privacy of patients.