A Healthy Mix of Barking, Burgers and Birkenstocks : The screening of ‘Threesome’ brought together a crowd of young and, um, <i> older </i> for a college film termed ‘an erotic buddy movie.’

The Scene: Monday’s premiere of TriStar’s “Threesome” at the Motion Picture Academy’s theater. A reception was held afterward in the lobby. The story of a romantically involved, college-student trio of mixed sexual orientation was described by guests as “an erotic buddy movie,” “ ‘Reality Bites’ mixed with ‘Jules and Jim,’ ” and “provocative, erotic, neurotic and sensual.”

*

Who Was There: The film’s stars--Lara Flynn Boyle, Josh Charles and Stephen Baldwin--writer-director Andrew Fleming, and producers Brad Krevoy and Steve Stabler. Among the 1,000 guests were Luke Perry, Jennifer and Meg Tilly, Blair Underwood, Lauren Holly, Chynna Phillips, Quentin Tarantino, and studio execs Stacey Lassally, Marc Platt and Buffy Shutt.

*

Most Truly Weird Trend: The fan who greets arriving stars with a piercing, dead-on imitation of a German shepherd barking to the tune of “Jingle Bells.” Even the Beverly Hills cops came over to investigate. Said one observer: “I think he’s trying to break into show business.” On this night, the barker couldn’t even get arrested.

*

Audience Review: Much impressed. Like this was a reason to go to film school. “It was intelligent ,” James Johnston said. “It was amazing they’d give us anything like that. They didn’t talk down to the audience. You were so along for the ride.”

*

Dress Mode: Extreme demographic mix. Half the crowd was over 40, the other half under 25. The older went for suits, the younger a mix of Generation X casual and slacker after-work--plaid shirts, nose rings, Birkenstocks, goatees and faux grunge. Looking at the crowd, one casting director said: “Hollywood’s always getting younger. I used to be one of the young ones, but now. . . .”

*

Chow: In keeping with the film’s college setting, there was “dorm food” from Ambrosia that included pizza, burgers and, uh, sushi. But the lobby was so crowded it was like holding a food tasting in a sauna.

*

Vocabulary: Taggers --guests along just for the ride. No ambition to break into Hollywood, they’re there just because they can be. As in the sentence: “They looked like screenwriters, but they turned out to be taggers.”

*

Pastimes: While the film screened, agents and execs watched the NCAA championship game with the kind of frenzied interest only gambling, or having a child on the team, inspires. The film’s budget was probably less than the money that changed hands when Arkansas won.