The movie musical has been through a dazzling evolution since the days of the talkies, from stage-bound hokum to brash on-location masterpieces to animated delights. Shoehorned in those, is the lamentable MTV genre, where a song-dense soundtrack of rock songs express the characters’ inner lives, only without the characters themselves singing. Footloose, even Top Gun, fall into the category. Occasionally, we still get the old school versions of classic musicals, like Chicago. Mamma Mia and the upcoming Les Miserables movie, as well as the TV show Glee.

But how well can you combine the ’80s brand of jukebox rock into a traditional musical format? Not well, judging by the disastrous Rock of Ages.

I went in with an open mind; I like musicals. So even during the opening credits, as Julianne Hough sings “Sister Christian” on a Greyhound bus while the driver and other riders chime in, I didn’t laugh mockingly … even though everyone else in the audience seemed to be. I put up with it as much as I could through ugly production numbers where characters looked less like they were dancing and were instead experiencing painful seizures. I gritted my teeth as Catherine Zeta-Jones, playing a right wing scold intent on censoring rock music, lead-footedly hoofed her number in a church. And while I actually enjoyed the clever sequence where Russell Brand and Alec Baldwin put a gay twist on “I Can’t Fight This Feeling Any Longer,” the truth is, the movie just doesn’t work. Nice try. But it’s terrible.

There’s no denying some nostalgic appeal to the story, set in Los Angeles in 1987 at the height of the Reagan Era and hard rock hair bands like Bon Jovi and Guns N’ Roses. (The set design in the Tower Records store alone is worth a chuckle or two.) And if you’re a fan of the likes of Foreigner and REO Speedwagon, well, there’s plenty of that here. But none of it comes together. In trying to make a film that looks like it is set in the 1980s, director Adam Shankman has made one that looks like it is from the 1980s, including flat cinematography, frantic editing, dumb plotting and corny acting. Shankman’s Hairspray was a Valentine; Rock of Ages is a musty postcard.

The plot is among its lesser achievements. Hough plays a Midwestern girl who moves to L.A. to make it at as a singer. She meets a bar-back (Diego Boneta, who will be a handsome man one day if he ever completes puberty) at a rock club on the Sunset Strip, and together they get involved in disparate paths in the rock scene, much of it centered around the hard-drinking weirdo rock god Stacie Jaxx (Tom Cruise).

A blind spot of Rock of Ages is how it never consistently distinguishes its camp factor from its sincerity. The film comes to a screeching halt at its midpoint in a deathly long scene between Jaxx and a prissy Rolling Stone reporter (Malin Akerman, exuding zero no sex appeal) which develops into a sex romp that sometimes seems comic, sometimes just sloppy.

The casting of Cruise is both clever and dumb; Cruise was actually a star of the caliber of Jaxx back in 1987, and to a degree, he still is, so the cynicism feels earned; but Cruise, who’ll be 50 in three weeks, is also past his prime as a live-fast-die-young rock hero. He sings his own songs, and he’s pretty good, but despite getting the swagger right he looks out of his element. You’re never quite sure whether he’s meant to be channeling Axl Rose or Nigel Tufnel.

On the other hand, Brand has never been more likable in a movie, and Baldwin  — a contemporary of Cruise with a different career path since about 1990 — lends a great comic presence.

The stage musical on which the film is based was an oddity for me, a show where Act 1 was terrible but Act 2 was great. I kept waiting for Rock of Ages to rock me like a hurricane. I’m still waiting.

One and a half stars. Opens Friday in wide release.