Four years after the cast of HBO’s “Entourage” bid farewell, the long-awaited movie version of the popular series premiered at New York City’s Paris Theater on Wednesday night to loud cheers and big laughs.

Cast members Kevin Connolly, Adrian Grenier, Kevin Dillon, Jerry Ferrara and Jeremy Piven reunited with creator Doug Ellin, who wrote and directed the 104-minute feature film, for the special screening.

“To be honest, I wasn’t sure if the movie was ever going to happen,” Dillon, 49, told Variety on the red carpet. “We all wanted to make a movie from the get-go, but things took so long and some things had to be resolved before we could start shooting. I was like, ‘It’s getting late now. People won’t be interested anymore. We have to get this done.’ So it was a relief that we actually did it.”

One reason for the delay was the film’s screenplay. “Writing a story that could sustain itself for an hour and half was the biggest challenge,” said Ellin, 47. “I sat down with Stephen Levinson and Rob Weiss and we talked about ideas as stories for months. Getting the script done was the hardest. Everything else was pretty easy. Mark Wahlberg said to me, ‘Write the script and I’ll get it made.'”

Fortunately, Warner Bros. greenlit the project for $25 million and filming begin in February 2014. Ellin said he had no worries whether the television series, which ran for eight seasons from 2004 to 2011, could translate into a crowd-pleasing film. “We were a cinematic show to start with. We were doing things that no one was doing on half hour television,” he said. “We shot live at YouTube concerts, we shot at the Cannes Film Festival, Sundance and in Vegas, so we were capable of telling a story on a larger scale.”

The comedy — out in theaters June 3 — picks up a few months where the television series ended. Behind the show’s comedic shenanigans and its portrayal of Hollywood’s glitz and glamour, the central theme of “Entourage” is the strong brotherhood between friends.

“The show is about loyalty and the idea of what matters in this life,” said Piven, 49, who won three consecutive Emmys for playing the ruthless and foul-mouthed agent Ari Gold. “Through thick and thin you have to stick together and be people of your word.”

Connolly, 41, added, “Friendship has always been the message behind ‘Entourage,'” he explained. “It’s about the unconditional love and support that these guys have for each other. I can relate to them. In my own life, family and friends are the most important thing.”

As for the actors stepping back into their famous roles, Piven says playing the brazen agent is “fun and a blast to play,” but it’s physically draining. “It can be a little taxing, but it’s all a part of it. I welcome it with open arms.”

Ferrara jumped at the chance to reprise his breakthrough role. “Being part of ‘Entourage’ is one of the best things that’s happened to me,” he said. “I was 23-years-old when we started the show and now I’m 35, so it’s changed everything for me and my family. I’m so thankful. If all of the stuff that comes with acting went away, I still already won. I succeeded. I made friends that I will have for the rest of my life.”

For Grenier, 38, playing movie star Vincent Chase is the opportunity to live a fantasy. “I get to have the fun that I never get to have in real life,” he said. “It’s a total escape for me to play Vincent. It’s a fun ride. As Vincent, I can let go of any troubles and have a good time.”

Following the screening, hundreds of guests crowded inside Midtown Manhattan’s nightclub Lavo for a night of reveling. Newcomer Sabina Gadecki, who plays Connolly’s love interest, snapped a few photos with her co-star while Grenier greeted well-wishers near the deejay booth. Dillon and his daughter Amy briefly mingled with Ellin, who was the toast of the after-party.

“I have 50 people here tonight from elementary school and another 50 from high school and college,” said Ellin, a Brooklyn native. “There’s people here who I named characters after. My friend Scott Lavin who Scott Caan played, Andrew Kline who Gary Cole played and everyone from this girl to that girl I put their names in the show. It’s a special night and I’m happy to celebrate with them.”