As parties go, the one generated by Richard O’Brien’s rock musical spoof The Rocky Horror Show just might be the longest on record. Happily, the raucous production for Memorial Auditorium’s Broadway Series South by City Stage of Wilmington keeps this unruly gala going in high (camp) style.

O’Brien’s inspired conceit, when the musical first opened in London in 1973, was to marry a few traditional horror movie staples (isolated castle, weird goings-on presided over by mad scientist, innocents who stumble in) with rock songs and some of the more outré trappings of then-current glam-rock sexual ambiguity. A hit in Britain, the show tanked in New York, after which, astonishingly, 20th Century-Fox financed a film version in 1975, directed by O’Brien’s collaborator Jim Sharman and featuring much of the London cast, including the staggeringly original Tim Curry. Equally oddly, the movie bombed in England but soon took on seemingly limitless life in the States as a midnight-movie unlike any ever seen, in which audience participation, such as the mocking lines shouted during pauses or in response to lyrics (“Say it!”) or the mass flicking of lighters during “Over at the Frankenstein Place,” were de rigueur, costuming optional. Thirty-five years later, The Rocky Horror Picture Show is still playing to large and enthusiastic cultists, some of whom may very likely be the children of kids who kitted themselves out as Magenta and Dr. Frank-N-Furter in the 1980s.

One of the more encouraging aspects of the movie’s phenomenon was the affectionate embrace by its young audience of characters who embody what one can only call a kind of cosmic pansexuality: not merely the emulation of the fishnet-and-garters wearing Frank-N-Furter, but a nearly complete lack of negativity regarding what conservatives like to call “the ick factor.” This attitude is refreshingly evident during the show at Memorial as well, both on-stage (as when a rainbow flag is exhibited) and off (the cheers that erupt in the audience when two of Transylvanian boys kiss). During the filming of the movie, Jim Sharman made some risible assurances to the press that Rocky Horror was some sort of morality play. O’Brien, who describes himself as “between” male and female, must have had a good laugh at that one.

The cast here is largely without blemish, and remarkably successful at eschewing any imitation of the now indelible performers from the movie. As the iconic innocents abroad in a land of debauchery they can scarcely imagine, Zack Simcoe is a suitably preposterous and stolid Brad, perfectly matched by Morganna Bridgers’ quintessentially virginal Janet. Caitlin Becka and Jeremiah Williams are equally effectual as their mirror images, Magenta and Riff Raff, Anthony David Lawson and Tim Marriott are admirably restrained as Narrator and Rocky respectively, and Cindy Colucci lends powerful vocal presence to her triple casting as the Usherette and — androgynously — both Eddie and Dr. Scott, less than fully effective only when called upon to project the more masculine passages. Jes Dugger’s Columbia suffers from a certain shrillness that occasionally renders her lines, spoken and sung, unintelligible.

The Rocky Horror Show rises or falls on its leading figure, and in H. Dean Jones, this production boasts a Frank-N-Furter to treasure, from his blue-dyed punk hairstyle to the Rockette-worthy high-kicks of which his shapely stockinged thighs are capable. As with everyone else in this spirited cast, his vocal range and abilities do more than justice to O’Brien’s curiously timeless songs.

Justin Smith has directed with assurance, imagination, and a wry understanding of the opportunities, comic and sexual: Brad and Janet “drive” an automobile made up of the bodies of the protean Transylvanian Phantoms; Fran-N-Furter’s dual seduction of Brad and Janet are performed, behind a curtain, in a very funny shadowed dumb-show; and unless I’m mistaken, Smith’s production also boasts a built-in “plant” in the form of a heckler who calls out most of the better lines you recall from being in the audience at the movie, in addition to several newer ones that are nearly as memorable.

Chiaki Ito’s musical direction keeps the high-octane score percolating madly but without overpowering the performers. Briton Campbell’s costumes are indebted to, but not slavish copies of, the originals; and Kevin Green’s choreography fizzes and pops without undue ostentation, as does Tara Nolan’s effective lighting.

This Rocky Horror Show, like the movie, is impervious to time warp. It’s got pelvic thrust.

It plays again on Sunday October 31, at 8:00 p.m., for Broadway Series South, in Raleigh’s Memorial Auditorium. For details, see our calendar.