ADVISORY: This story contains mild spoilers for HBO’s Mare of Easttown.

We were standing across the street from Marcus Hook Pharmacy. Mare of Easttown assistant location manager Rudi Fischer was shooting the breeze with me and Inquirer photographer Tom Gralish. We were in front of a bunch of Delco rowhouses, a guy smoking a cigarette on the steps of one behind us.

Down the street was a huge Delaware County refinery. In the other direction, the Delaware state line. And within just a few minutes’ drive, many of the locations that made their way into the HBO series that vaulted Delco and its streetscapes to global fame over the last two months.

The stoop smoker got our attention the way many people do in Delco: By blurting out an observation as though we strangers were all old friends hanging at a bar.

“That fish tank that’s in the show?” Cliff Light declared. “I sold it to the fish store.”

Say what?

I’d found Fischer to help pin down all the places where the show had been shot in Delco, Chester County, Montgomery County, and Philadelphia. Guessing the locations had lit up social media for weeks through the series finale last Sunday.

But instead, we were face-to-face at this moment, in front of this random guy, with the show’s big subplot: The everyone-knows-everyone quality of life in Delco, which to outsiders seems an impossible, overblown and clearly dysfunctional coziness for a Philly suburb of 560,000 people.

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Delco is a social spider web that pulls you into someone else’s business through one or two degrees of separation every single day. Delco Catholic high school grad Brad Ingelsby (Archbishop Carroll), whose series-creating vision demanded giving Delco and its glorious accent and affect high billing as a character unto itself, would have found this fish-tank convo poetic.

The tank, as the Mare-obsessed know, was bought by Mare Sheehan for her grandson’s turtle. What you only know now, because of this gentleman on the stoop, is that it came from a shop a few minutes’ drive from the pharmacy across from his house. It’s an old tank he’d unloaded some time ago.

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“The owner told me,” Light said. “Me and him are friends. Aquarium World. That’s right up in Aston, right across the street from the best cheesesteaks you’ll get.”

Delco. Right there.

Fischer had brought me to this corner because a number of Mare scenes were shot within a few blocks of it. One outside the pharmacy itself. Many locations were chosen for the simple reason of their proximity to Sun Center Studios nearby, or because other scenes were being shot nearby.

A block away, we breezed into New English Style Pizza. Met owner Chris Kolionis. Found out he was baking pizzas as props during filming of a scene there in November 2020 when a priest character shows up to pick up a food order. An ensuing dramatic scene took place outside the back exit in the shop’s darkly lit parking lot, too.

“It was exciting,” Kolionis said, as Fischer, who helped find and handle production logistics at the shop as part of his work with a team of Mare location managers, stood near one of the booths that figured prominently in the episode.

Locations scout Dan Gorman was the Delco native who connected me to Fischer for this column. Gorman had helped find spots for Silver Linings Playbook and Creed. I had written about him a few years back. For sure, I figured, a Delco guy such as himself had worked Mare.

I was wrong.

Fischer is a Horsham kid. Montco. But with a location scouting archive that’s as deep as a fixer’s contacts list, brimming with locations he’s found through the years in Delco and across the region.

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I asked him to lay out where a lot of scenes that filmmakers ultimately agreed to use were shot.

“The houses. Most of your bilevel houses, like Mare’s house, her [former] husband’s house, which literally is right behind her house, her best friend’s house, those houses are all in Wallingford.

“The other houses where, like, the chase happens in that first episode? Those were all in Marcus Hook,” Fischer continued. “She’s chasing her friend’s brother ... where the older couple lived, that’s Marcus Hook also.”

The interior of Mare’s house was built on a stage at Sun Center, as were the insides of the police station where Mare, a detective, worked. The show turned an old Coatesville train station on Fleetwood Street into the facade of the fictional Easttown police station.

A waterfront scene where Mare and Detective Colin Zabel were shown talking in Episode 5 was shot on a pier beneath the Commodore Barry Bridge right next to Subaru Park, the soccer stadium in Chester.

The decrepit building where an explosive scene took place later that episode involving Zabel was a short drive away from there, inside an empty building near Route 452 and Market Street off the main drag in Marcus Hook.

The dive bar where Mare met novelist Richard (Guy Pearce) was right off Market, too — the Star Hotel Bar. Scenes for a lavish party for Richard were shot inside Girard College’s library, and the school’s Founders Hall was used for a wedding reception scene.

A gas station and convenience store that made recurring appearances in the show was in Phoenixville. Zabel’s mother’s house was on a street in the Beverly Hills section of Upper Darby near Naylor’s Run Park.

Finally, toward the season finale, a momentous scene near a waterfall was actually the Wissahickon Creek near Valley Green along Fairmount Park’s Forbidden Drive in Philadelphia. (A fight scene in the woods from far earlier in the series was filmed a short hike away from that, near the Henry Avenue Bridge at the Wissahickon.)

After 17 years working on dozens of projects as a location scout or manager, Fischer said that Mare is the one beyond all others that has most lit up his phone. He is usually a background guy. But this show? Everyone wants to talk to him.

“I’ve gotten phone calls from people I haven’t talked to in years,” said the Hatboro-Horsham High graduate.

He told me that members of the out-of-town crew who worked on preparing and managing filming locations with him arrived skeptical about the Delco story line in the script. They couldn’t fathom the connections among people were anything but gross exaggerations.

Then it came time to leave. And they realized they had been dead wrong.

“They formed lasting relationships. ... People would stop to talk to them. When they stopped inside a bar to have a conversation with the owner, people would stop and talk to them in the bar. It was like they were known.

“It was like,” Fischer added, “they were from Delaware County.”