• Courtesy of Colin Thompson
• Russell Posner (left) takes direction from Colin Thompson on the set of 'Light Years'

Director Colin Thompson's third feature film, Light Years, did not turn out as planned. The Shelburne-based filmmaker originally set out to shoot a straightforward buddy comedy based on his experiences growing up in Vermont in the late '90s. Most importantly, Thompson was adamant that he would not appear in the picture. He'd had enough on-screen time after starring in his previous features, 2016 relationship dramedy It's Us and 2014 coming-of-age story Loser's Crown.

But fate had other plans. After a number of high-profile actors dropped out of the project and financing woes took their toll, Thompson, 37, figured out a way to rework the story under the new constraints: He would play almost all of the parts himself.

It's not as weird as it sounds. In the revised script, Thompson plays a character — essentially himself — who magically visits his past via the power of drugs. Through the haze of psilocybin mushrooms, he relives a night of partying and self-discovery spent with his best friend, Briggs, portrayed by up-and-coming actor Russell Posner. As the story and the trip progress, Thompson literally starts seeing himself in the face of everyone he encounters, except Briggs.

"I wanted the story to be about best friends at that age ... a love story between two heterosexual teenage dudes, [with] nobody else in the world," Thompson said during a recent video chat with Posner and Seven Days.

• Courtesy of Colin Thompson
• Colin Thompson (left) and Andrew Briggs in June 2001

Briggs is based on Thompson's real-life best friend, Andrew Briggs, who died of a drug overdose in 2001. Though Posner's only exposure to Briggs was through photographs and stories of people who knew him, the 23-year-old actor delivered a stunningly accurate and detailed portrayal. I know this because — full disclosure — I was in Briggs' homeroom at Champlain Valley Union High School. (Twist! You're reading a first-person piece.)

I wasn't exactly friends with Briggs in high school, or with Thompson, for that matter. Social stratification meant that my theater friends and I were probably partying in the next field over from the Thompson-Briggs crew. Since I was insecure outside my thespian bubble, I spent a lot of time quietly observing the people around me. And spending about 20 minutes a day with Briggs for four years of high school gave me ample time for observation.

Briggs died a few months after graduation. Though I casually reflected on him over the decades, I didn't think much about his idiosyncracies, such as his exaggerated phrasing and grandiose lexicon.

But in 2019, as I marveled at Posner's performance during the local premiere of Light Years, the memories came flooding back. In every wide-eyed, shit-eating grin, every twitch, every utterance of the phrase "So sick," I saw pure truth. It was astonishing.

"As soon as I read the material, I was like, 'I need to be this kid,'" Posner said.

Thompson knew as soon as he watched Posner's audition tape that he was the one. He said it was crucial to get some extra time with the actor in Vermont before the rest of the cast and crew assembled for shooting, which took place entirely in the state. He especially wanted Posner to soak up some memories from Thompson's dad, Larry, who is played in the film by Vermont resident Ryan Miller of indie-rock band Guster.

"We developed our own kind of language," Thompson said. "It was a good excuse to act like a teenager again."

And what better way for two adult actors to get to know each other, especially ones who are about to play drugged-out teenagers, than to do some drugs? Before the start of shooting, Thompson and Posner munched a few caps and headed out for a hike.

"We hardly spoke for two hours," Thompson said. "I abandoned all of my reservations and insecurities. I'm sounding cheesy, but we got each other's vibration that day."

When Posner first read the Light Years script, he didn't know that the Briggs character was based on a real person, let alone one who never made it to adulthood.

"There were definitely a couple times — especially when I met [Briggs'] mom — I was like, 'OK, lay low and don't insult any part of his being,'" Posner said. "I trusted that [Thompson] wasn't going to let me fuck it up."

Part of that assuredness came from the intensity of Thompson's direction.

"You know you have Colin's trust when he's kicking the shit out of you," Posner said. Though he hasn't been in the biz long, the actor has worked with heavy-hitting directors (ahem, M. Night Shyamalan) and appeared on high-profile TV shows such as "The Deuce" and "The Politician." He noted a drastic difference between Thompson's directorial style and that of some of the other directors with whom he's worked.

"He's not gonna be like, 'Maybe try it this way,'" Posner said in a mock-pretentious tone. "[Thompson's style] is very honest, and I really appreciated it."

Briggs' mother, Joan, who still lives in the area, moved out of her condo for three days so the crew could shoot a few crucial scenes there. Later, she attended the local premiere.

"I really went into the premiere pretty cold," she said by phone. "But I trust Colin implicitly."

I can't imagine the strange, overwhelming feelings she must have had that night. Joan Briggs ended up not only loving the film, she said, but also approving of Posner's version of her son.

"I thought he was very good," she said. "He is an amazing actor."

More than a vehicle to conjure Briggs, Thompson's script revived the real-life pair's "je ne sais quoi," as Joan put it.

"What it made me think of were all the times Colin came over to retrieve Andrew, and me trying to make Colin walk around and look at my plants," she reminisced. "Andrew would be going, 'Let's bounce, let's go.' It was just — it was Colin and Andrew. What can I say?"

While the film reveals Posner's and Thompson's talents as actor and director, respectively, I found myself thinking in more metaphysical terms after watching the premiere. If Thompson can perfectly relay Briggs' essence to someone who's never even seen a video of him, then, in a way, Briggs isn't dead. He lives inside Thompson and the other people who loved him.

Now I'm the one sounding cheesy.