Science fiction. Rock ballads. Underwear?

Forbidden Planet Productions will be performing its annual production of “The Rocky Horror Picture Show” this coming Thursday, Friday and Saturday.

Forbidden Planet has been performing “Rocky Horror” since the company’s founding 14 years ago. The company’s name, “Forbidden Planet,” draws from the show – a line from the first song, “Science Fiction Double Feature.”

Katherine Nelson, executive producer of Forbidden Planet, characterized the their performance of “Rocky Horror” as a campus tradition.

“It’s very different from everything else we do,” she said.

Though Forbidden Planet typically performs two musicals and one or two straight plays a semester, Nelson said “Rocky Horror” is their primary event. While other shows are performed in the University’s smaller venues – Lisner downstage or Mitchell Theater – the show this weekend is in the Marvin Center Grand Ballroom.

Even in this larger space, 50 to 100 people are expected to be turned away each night.

“We just don’t have enough seating for every person in line,” said director Paul Rozenberg, who has directed the show for the past three years. Both he and Nelson suggest arriving at least a half-hour in advance to ensure admission and avoid the long lines at the door.

But don’t be dissuaded by the lines, they said. Ensemble members from the production – fondly dubbed “trannies” – ask trivia questions to people waiting in line. Those who answer incorrectly, “Rocky Horror virgins,” are brought on stage to be part of the show.

“It adds a whole new dimension,” Nelson said. “The show becomes interactive.”

Audience participation is not just limited to the lucky few pulled on stage. All audience members are instructed to yell “asshole” every time an actor says the name Brad Majors and to yell “slut” whenever an actor says the name Janet Weiss – the female and male leads of the show. Dancing to the “Time Warp” is also encouraged and expected of the audience.

“We really want the audience to participate,” Rozenberg said. “Everyone knows the song.”

Preparations for the show began over the summer and auditions were held the second week of school. After singing 30 seconds of a song, prospective actors were asked whether they felt comfortable being in their underwear on stage.

“During the auditions they think we’re joking, but we have to know if you’ll be uncomfortable doing this,” Nelson said. “The cast is always in their underwear.”

This year’s “Rocky Horror” will resemble previous years’ in terms of content and format – with actors lip-synching movie dialogue but actually singing songs. But the audience can expect more risqué choreography this year, Rozenberg said.

“Our choreographer put a much sexier edge on the choreography, which goes really well with the show,” he said.

This production also marks the end of Rozenberg’s Rocky Horror career at the University. This not only includes directing for the past three years, but starring as Doctor Frankenfurter for the past four years.

“Rocky Horror” will be performed this Thursday at 9:30 p.m. and Friday and Saturday night at midnight in the Marvin Center Grand Ballroom. Tickets are $5.