It’s some kinda strange magic

OK, so what’s so magical about an alien and roller disco? How to explain the miracle that took a flop of a movie and turned it into a first-rate musical? Perhaps it’s that far-fetched plot on the screen is more acceptable on the stage, where the real test is in the song-and-dance quotient. Or maybe it’s just the nostalgia factor. In any case, Xanadu is first-rate fun, with Kira (the alien) playing musical muse for Sonny (the artist) on the boards of a disco roller rink to an ELO-induced fantasia of music. It also raises the question: Why isn’t there a disco-pop Greek chorus at the Midtown ice rink?

Xanadu; 8 p.m. Tuesday and Wednesday; 2 and 8 p.m. Thursday; 8 p.m. Friday; 2 and 8 p.m. Saturday; 2 and 7:30 p.m. Sunday; $18-$65. Broadway Sacramento at the Community Center Theater, 1301 L Street; (916) 557-1999; www.californiamusicaltheatre.com. Through January 10.