The tap shoes are on, the ballet slippers tied and the members of the chorus line are ready to kick their heels high.

And on Thursday night, they will do so as the curtain rises at the Martha’s Vineyard Regional High School Performing Arts Center for the opening performance of A Chorus Line, the longest-running American musical on Broadway.

To the untrained eye the scene was this: two adults on stage, one speaking in an English accent, the other in a cross between a buccaneer’s snarl and a schoolyard bully. Five kids looked expectantly at their director, an adult on hands and knees, who crawled dramatically across the Vineyard Playhouse stage. The cast watched seriously for a good half-minute before all, director included, erupted into uncontrollable, side-clutching giggles.

“I don’t even like musicals,” says Donna Swift, writer and producer of more than a dozen musicals and founder and excutiver director of Troubled Shores Inc., a not-for-profit theatre organization. She is sitting on a newly painted stage prop for her latest production — a reworking of the Seventies musical Godspell — in the cafeteria of the Oak Bluffs elementary school.

“I try to put that in my writing, though — to say, ‘Look how ridiculous this is — I’m singing now.’”