At first, I thought the bearded dude at my door was yet another Sierra Club volunteer I’d have to shoo away. Instead, he was a movie location guy knocking to say they’d be shooting on our block.

A few weeks later, I’m dressed in a polyester suit and behind the wheel of a vintage limo with actors Liam Neeson and Marton Csokas in the back seat. It is a dramatic point in the film and Pretend FBI Agent Torpy, known namelessly as “Limo Driver,” was waiting for his cue to hit the gas and drive off.

My acting skills, which are nonexistent, have nothing to do with the role. My 1950s flat top snagged the part. And perhaps my dour visage.

They’re shooting “Felt,” a movie about FBI deputy director Mark Felt, the mysterious Deep Throat in the Watergate scandal. I saw a casting call seeking 1970s FBI types. I emailed my head shot, saying my haircut screams 1972 FBI agent. Or Nixon aide H.R. Haldeman. Soon, I got a call.

Like most everyone, I have dreamed about seeing my mug on the big screen. And to be honest, I feel a bit entitled: For years, I’ve paid for guys with camera booms to block Atlanta streets.

Georgia has bet big on the film bidness. A recent study by Georgia State University said the tax credit given to movie outfits (which can range between 20 and 30 percent of a project’s budget) cost the state an estimated $925 million between 2009 and 2014.

Naturally, those who have opened up the checkbooks say it is working. Last July, Gov. Nathan Film Buff said the 248 film and TV productions shot the previous fiscal year represented $1.7 billion of spending here.

The total economic impact was $6 billion, he said. But those “multiplier effect” spending estimates are often as inventive as Hollywood accounting.

On our street, the site coordinators threw money around like confetti to win over the neighbors, renting driveways at $500 a pop.

However, I live at the far end of the block and saw none of this largess, although a four-seat, steel-constructed, generator-powered outhouse was parked across from my driveway.

I didn’t mind, I saw it as taking one for Team Felt. And perhaps a famous bottom graced my cul-de-sac.

(I did get $8 an hour as a non-talking extra.)

The special effects guys made it snow for a winter scene, spewing a truckload of crushed ice on lawns. Unfortunately, it was 80 degrees and sunny because it’s mid-May and it’s Georgia. So it melted and they had to do it again that night. The ice cube vendor happily returned with another load.

It gets expensive — at one point in between scenes, I counted 47 people working within my sight, from Liam Neeson and director Peter Landesman (“Concussion”) to the grip guys and cameramen to the DeKalb cop working an extra job.

Time is money and these suckers hump. Unless they’re standing around. A lot of that happens. Everyone was professional and cordial, from the guy at my door, to the location people, to my handler, Randy the car guy from Jackson, Ga., who was the minder for the 1968 Cadillac Fleetwood that measured 19 feet long and sounded like an M1 tank with a shoddy muffler.

Even actress Diane Lane took a minute out from movie stardom to wander across the street and hug my neighbor Carol on her birthday.

The production was here for two weeks, shooting from 9 p.m. to 6 a.m. My DeKalb County street, full of 1960s homes, subbed as an early 1970s Washington-area neighborhood. My neighbors saw the event as a backdrop for a continual community mixer.

Gaggles of curious, star-struck residents, myself included, milled about across the street from the production or hobnobbed with crew during the down times. We rarely knew what was going on, but somehow it all seemed important.

I ended up in four scenes, two shot on my block after midnight and two driving the road beast on Freedom Parkway during rush hour, surrounded by an armada of vintage cars as the camera rolled. This being Atlanta, a 2012 SUV tried to sneak into the scene. And the limo toyed with overheating.

I normally don’t get excited about meeting people, it’s my job to chat with folks who’d normally have nothing to do with me, whether it be an ex-president or a crack dealer. But I admit to being a wee bit star struck here; this was a movie that touched on journalism and had the world’s most famous Irishman not named Bono (my mom’s from Limerick).

Liam Neeson wasn’t a neighbor-hugger as was his co-star. But he was polite and funny and grumbled about his itchy wig.

I didn’t push much conversation because I was a movie extra. They’re supposed to shut up and stay out of the way.

But I couldn’t help but make note of a true cosmic coincidence in the street right outside the limousine’s door. Years ago, the county rebuilt a sewer manhole there and my sons Fred and Liam etched their names into the wet cement.

I dragged director Landesman over and pointed down at “Liam” in cement, right there next to the limo.

It’s like the Torpy clan marked off this space a decade in advance, probably the only place in the Southeast where “Liam” is carved into public property — right next to a limo with Liam Neeson inside.

So, I suppose this was all preordained.

“Wow, how cool is that?” Landesman noted before heading into another take.

The next day, my neighbors awoke to find most of the equipment gone and crews rolling up the sheets of background snow. There was a collective day-after-Christmas melancholy.

The circus had moved on and regular life had returned.