It’s difficult to call “Rock of Ages” an all-out flop.

Yes, one of the three story lines feels like an unfortunate sequel to that “American Idol” movie, “From Justin to Kelly.” And true, the story has no idea where it’s going, is altogether too long, and director Adam Shankman takes every opportunity to shock and offend audiences. But the supporting cast in “Rock of Ages” is so good, it’s almost impossible to write the film off as a movie better unseen.

And yet, that’s where it lands.

Not even the sincerest camp from Tom Cruise, Paul Giamiatti, Alec Baldwin and Catherine Zeta-Jones is enough to elevate this to story to a guilty pleasure.

Set in Los Angeles during the late 1980s, two aspiring musicians (Diego Boneta and Julianne Hough) try to make their way to fame and fortune while waiting tables at the legendary Bourbon Room — a rock club which regularly headlines rock and roll’s biggest names.

While the two dabble through a paint-by-numbers love story, conservative watch groups, led by the politically driven Patricia Whitmore (Zeta-Jones), pool their resources to bring down the city’s seediest establishments, naming the Bourbon Room as public enemy No. 1.

The Bourbon Room’s owner (Baldwin), already against the ropes because of failing finances, hopes a comeback performance from music-god Stacee Jaxx (Cruise) will square away the bar’s financial woes, silence the churchgoers, and once again put Jaxx and the Bourbon Room at the center of music greatness.

As expected, the three stories find their way to a single karaoke ending, though at no point do the individual tales find a compelling reason for audiences to care.

The problem with “Rock of Ages,” the glaring problem, is that there’s no real audience for the film.

There’s no data anywhere to support the idea that rock fans of the '80s evolved into musical theater lovers in their mid-30s. Musical theater lovers of today won’t get the endless inside jokes derived from Journey, Poison or Night Ranger lyrics. And for parents simply looking to wax nostalgic with some of their favorite classic ditties, the film is so unnecessarily racy that it would turn any date night into a series of awkward stares and manly promises like, “I had my eyes closed through that whole Foreigner scene.”

Speaking of Foreigner, there’s an almost pornographic moment in the film where, during our screening, a dad grabbed his daughter by the hand and walked her out of the theater. The general consensus from those sitting in the audience probably wasn’t “Good for you, Dad,” but instead, “I can’t believe it took you this long.”

It was disheartening to see some really great elements wasted on this movie. Giamatti may have been the only cast member who couldn’t sing, but his portrayal of sleazy music manager Paul Gill worked so well with Cruise’s questionably insane Jaxx, that you might end up wondering why they weren’t the focus of the entire story.

Likewise, Baldwin and Russell Brand earn some genuinely funny moments, though they’re almost always interrupted by the charisma-vacuums, Boneta and Hough.

But like a chocolate taco salad smothered in ranch dressing, the great components of this film never mix with any level of success, leaving the terrible aspects with no redeeming substance to hide behind.

Overall, the film gets 2 stars and is rated PG-13 for sexual content, suggestive dancing, some heavy drinking and language.

You can contact Travis at [email protected]