The decaying vacant house at Ella and Stella Streets sits just across from Hope Park in West Kensington's bustling heroin bazaar.
Outside the back door are a half-dozen spent syringes, some with the needles severed off. Inside, dozens of white syringe wrappers form a snowcap on a layer of deep brown mud and a kaleidoscopic sprinkling of trash.
The ground-floor windows are boarded up, making Officer Jeff Stauffer's flashlight the only beam of light to pierce the quiet darkness inside.
Heroin "is used in there nonstop," he says through the empty rear door frame, slowly inching his way from the overcast sunlight into the filth.
Stauffer and his partner, Officer Joseph Ryan, 10-year veterans of the 24th District, patrol some of the most drug-infested blocks in the nation - open-air markets for heroin, marijuana, crack cocaine, PCP.
Their turf is pockmarked with dozens of these deteriorating vacant rowhouses, an essential tool of the drug trade: a place to hide the stash, a place to get high.
Alleyways here are buried under mountains of garbage, abandoned cars peppered with neon-hued crack caps. Users sometimes shoot up in the neighborhood's nooks and crannies; others get high in playgrounds or on public sidewalks.
Like two fishermen stuck in a swale of choppy waters, Stauffer and Ryan circle a square mile of this neighborhood in their SUV, searching for drug deals, robberies, assaults.
Riding along with them on the night shift gives a glimpse at a rough slice of the city, a district with more than 3,000 drug arrests per year - five times as many as in the nearby 26th District, which covers Fishtown and lower Kensington.
"Nothing," Stauffer says, "is out of the ordinary."
A few steps into the house at Ella and Stella, Stauffer shouts to try to rustle up whoever might be hiding in the shadows.
Hearing nothing, he's quickly had enough. If no one's inside, there's no sense in getting a needle stuck in his shoe.
Walking back out the rear door, his feet brush over tiny empty ziplock bags, the size of thumbnails. Heroin packets, he says: 5, 10 bucks a pop.
Thousands are sold around here every day.
"It comes down to what the demand is," Stauffer shrugs, heading back to the SUV to resume his night on patrol.
"The gun grid." That's what police have dubbed the center of Stauffer and Ryan's patrol area. Roughly a three-by-four-block trapezoid, it resembles a rectangle with a triangle attached to the right side.
Somerset Street is its southern floor, walled off by B Street to the west and Kensington Avenue to the east. Indiana Avenue is its northern ceiling, a hot corridor for drug dealing.
The surrounding territory was christened "The Badlands" decades ago, and there's not much indication that things have changed.
"This area is so saturated," Stauffer says, cruising the grid after dark, "you could let someone go with drugs, walk two blocks down, and lock somebody else up."
An early rain shower on this unseasonably warm March night appears to have washed away the regular players, Stauffer says. Even Hope Park - the shabby plot of grass just outside the gun grid where people sit on plastic milk crates - is calm as the sun goes down.
Action is an undeniable lure of police work, and part of why Stauffer and Ryan signed up for the job. But neither is a danger-junkie: In their early 30s, both are married with houses in the Northeast; Ryan has a young son.
They've spent their entire young careers in the 24th District, and both have higher hopes. Ryan, soft-spoken and baby-faced, thinks of rising into a prestigious investigative unit someday. Stauffer, who keeps his head shaved and is quick with a joke, has toyed with the idea of becoming a district captain - although he's wary of the stress.
"I lost all my hair from this job," he cracks.
While their shift passes, the two officers encounter minor offenses that might rankle police elsewhere: the scent of marijuana wafting into the SUV, two men scurrying away from each other and purposely dropping what could be drugs on the ground.
But here, by West Kensington standards, the streets appear largely quiet - a break from what Stauffer and Ryan call the uninterrupted flow of drugs and violence.
"It's a little depressing sometimes," Ryan admits, explaining that even with attempts to cool off specific blocks - through patrol activity or concentrated pedestrian stops - crime just migrates elsewhere.
Maria Quiñones-Sánchez, who represents Kensington in City Council, echoes Ryan's frustration. For years, she believes, city agencies have grown content with what she calls a containment strategy: limiting drugs and crime to a certain radius, then taking occasional, one-time stabs at disruption, such as drug sweeps or demolishing a handful of vacant structures.
"As long as it's contained to that area, there doesn't seem to be the political will to put forth the political resources" to comprehensively address crime and blight, she said.
Pastor Burton Gates, who founded Liberty Baptist Church on Indiana Avenue in 2009, knows the challenges. Gates, his wife, and three children live in a house down the street from the church; his daughter once fell and got a used needle stuck in her hand.
And when he arrived in the neighborhood, Gates - a recovering addict himself who moved to the city from Arkansas - blasted a recording of the Bible from church loudspeakers to prevent drug dealing from taking place outside his front door.
"They used to hide dope right along the [church] fence," he says.
Gates' congregation now stands at more than 100-strong, he says, and he appreciates the officers who work this beat.
"It almost is anarchy [here]," he says. "But it'd be complete anarchy if they ever gave up."
As Stauffer and Ryan roll toward the end of their shift at midnight, a computer screen glows in the SUV's center console.
Active radio calls are almost nonexistent. The streets of the gun grid are nearly empty.
It's an unusually slow night, Stauffer says, but patrol work can be that way.
"Ten percent [of the job] is hot," he says. "But hot is really hot."
After a decade working the same turf, Stauffer and Ryan admit they imagine ways to escape: retiring to a house on a farm, becoming a beach bum.
"These blocks have been here for years," Stauffer says as the SUV rumbles through the corridors of West Kensington rowhouses. "And it doesn't really change."
Overnight relief is about to move in, so Stauffer turns out of the grid and heads back to the station.
The sun has set on one shift. Tomorrow, another will begin.