Even in an era when some people chat on their cellphones in movie theaters during the show, it's not considered good form to shout rude remarks at the characters on the screen — with one exception.
At a midnight showing of "The Rocky Horror Picture Show," zingers from the crowd are all part of the show.
Fans often dress as characters in the film, including the iconic, cross-dressing, mad scientist Dr. Frank N. Furter, clad in a black lace-up vest, black briefs with garters attached, fishnet stockings and high heels.
Sonoma County audiences will get opportunities this fall to revisit the self-described "sweet transvestite from Transsexual, Transylvania" in both his stage and screen incarnations.
Santa Rosa's 6th Street Playhouse marks the 40th anniversary of the original London stage debut of the musical play, "The Rocky Horror Show," with its own new production opening Sept. 20.
And the Phoenix Theater in Petaluma will screen the 1975 film version, "The Rocky Horror Picture Show," starring Tim Curry as Frank, on Oct. 18.
"The film has the longest theatrical release in history," said Craig Miller, artistic director at 6th Street Playhouse. It has continued to play at cinemas worldwide for the past 38 years.
In keeping with the cult film's long-established tradition, there will be a live, costumed "shadow cast," performing the entire show right along with the actors on the screen.
"The evolution of the tradition started primarily in New York back in the '70s," said Nate Havoc of the all-volunteer troupe Barely Legal, which performs onstage at "Rocky Horror" screenings all over Northern California.
"There was a group of people that would go to the movie every Saturday night," he said. "Slowly but surely, people began to dress up like their favorite characters. Then they started to get in front of the screen and act out scenes."
Now there are groups like Barely Legal that hold auditions for every role in the film and come to screenings in detailed, accurate costumes, armed with all of the appropriate props.
The 6th Street Playhouse production will be a more traditional theatrical presentation, minus the movie screen, with a live cast singing and speaking all of the roles, accompanied by a live band.
However, the audience still will be encouraged to come in costume, and there will be costume contests on opening night and every Saturday night of the run.
"The Rocky Horror Show" is scheduled to continue through Oct. 13, and the 6th Street Playhouse also plans to stage a few midnight encores closer to Halloween.
One attraction that Miller, who is directing this production, promises "Rocky Horror" fans is the full score of the original stage version, including much more than just the familiar favorite numbers from the film version, such as "Time Warp" and "Dammit, Janet."
"The film excised several of the songs from the original stage production," Miller said. "Some of my favorite music from the musical was cut when it was turned into a film."
While the film version of "Rocky Horror" has been shown continuously all over the world for the past 38 years, stage productions of the original play are not so common.
Aside from Santa Rosa's production, the only other current West Coast production of the show is in Aberdeen, Wash., Miller said. "The Rocky Horror Show" was last staged in Sonoma County by the Summer Repertory Theatre at Santa Rosa Junior College in 2003.