Greg Sestero might be one of the best real-life examples of someone who put the adage “if life gives you lemons, make lemonade” into practice. The longtime South Pasadena resident was a struggling actor in 2002 when he was cast by his eccentric fellow acting course classmate Tommy Wiseau to co-star in an independent film called “The Room.”

What seemed like a decent career break turned into one of the strangest experiences of his life, resulting in a movie that is widely regarded as one of the worst movies of all time. Yet rather than slipping through the cracks, “The Room” became a worldwide cult sensation, leading Sestero into an even more unexpected career direction when he was signed to write the memoir “The Disaster Artist” about the making of the film.

Co-authored with veteran journalist Tom Bissell, that 2013 tome became a critically acclaimed national bestseller, inspiring a film of its own. The resulting movie earned its director/star James Franco a Golden Globe Award for Best Actor-Comedy or Musical and nominations for his direction as well as for Best Picture, and an Oscar nomination for Best Adapted Screenplay.

The resulting awards-season party circuit proved to be the most unexpected and memorable time of his life. Sestero will discuss his wild ride at 7 p.m. Friday when he sits down for a Q&A with this writer following a screening of “The Disaster Artist” at the South Pasadena Public Library’s Community Room, 1115 El Centro St., South Pasadena.

“It was interesting for me because I didn’t expect anything from ‘The Room’ to happen and didn’t expect anyone to see it,” says Sestero. “When people started seeing it, I was curious to see if people saw the same things in Tony that I saw when I first met him. I didn’t put passion or money into the movie, I was just there observing everything.

I never took it personally because it wasn’t my movie, but I knew the story behind the making was one of the most insane stories I’d ever heard, Hollywood or not,” he continues. “And I thought that story could make its own great movie, if told and approached properly. That became my goal — instead of trying to use ‘The Room’ to make it as an actor, I realized ‘You’re gonna have to take steps outside of that, explain who you are and what this was all about.’ Ultimately, what a great turnaround: making a great movie about the experience of making what’s called one of the worst movies ever made.”

The seemingly simple yet laughably convoluted story of a man who discovers that the love of his life is cheating on him with his best friend and the tragic consequences that ensue, “The Room” was intended to be a passionately serious showcase for the acting, writing and directing skills of Wiseau. A mysterious figure who has never publicly stated what country he’s from, Wiseau has an almost impenetrable accent that helped fuel derision from audience members straining to understand anything he said.

Wiseau also became notorious for claiming to spend $6 million on the making of the threadbare-looking movie. Yet he had the last laugh when he embraced rather than hid from the explosive laughter the film received at early screenings, and in the great tradition of showman P.T. Barnum, he turned the “The Room” into an audience-interactive, midnight-movie sensation that continues to be a hit in more than 25 cities worldwide.

“My initial reaction to ‘The Room’ script was amazement, and I’ve done readings at public events and every line gets a laugh,” says Sestero, who wrote the script for a movie called “Best F(r)iends” that he starred in with Wiseau and was released in June. “All you have to do is read it aloud with people and it delivers huge laughs in special ways. How Tommy views the world and human interaction lends itself to a lot of comedy.”

Coming through the other side of all the insanity of “The Room” to mingle with Hollywood superstars such as Tom Hanks, Oprah Winfrey and Sharon Stone at Oscar-season parties for “The Disaster Artist” proved to be another form of vindication.

“It’s not something I ever expected, but it was incredibly rewarding to finally create something that made it there,” says Sestero. “It shows you can never stop creating. One day you can make something considered terrible, the next day it’s great. Never get too high, too low, just hope to keep making things. I think in some ways people admired his making his own film and keeping it alive 15 years.

“‘The Room’ is still here and at some point you have to call it a success,” he concludes. “My family was shocked. I think they were as dumbfounded as anyone that this worked on some level.”

Greg Sestero discusses “The Disaster Artist” after a screening of the film at 7 p.m. Friday at the South Pasadena Public Library Community Room, 1115 El Centro St., South Pasadena. Admission is free. Call (626) 403-7340.