Say what you will about the genre, but that two headlining bands and an opener who haven't had a hit in more than 20 years can draw a crowd of more than 12,000 to the Cynthia Woods Mitchell Pavilion on a muggy Saturday night is an impressive feat.

The Def Leppard/Poison double bill, supported by opening act Lita Ford, was dubbed the "Rock of Ages Tour," after the campy rockstar musical starring Tom Cruise that hit theaters this summer. "Ages" was an appropriate theme for the night as aging hair metal fans with much less hair than they had in 1988 rocked as hard as they could, with some rising to the challenge more than others.

Def Leppard and Poison are no commercial slouches. The two bands have combined for 25 Top 40 hits and 150 million albums sold worldwide, a figure that is unfathomable even in Camp Adele these days.

Rocker-turned-realty star Brett Michaels led Poison through an hour-long hits-heavy set that featured "Fallen Angel," "Your Mama Don't Dance," and "Every Rose Has Its Thorn," a guilty pleasure that saw thousands of 80s-esque lighters and 00s-esque cell phone alight under the Pavilion's canopy and atop the hill. The scene made for uninhibited fun. Ballads aside, Poison is at its best with innuendo-filled hits, such as "Talk Dirty to Me" and "Unskinny Bop," both of which drew loud responses.

The set closer was "Nothing But A Good Time," the song that put Poison on the big rock map. Throughout the set, Michaels thanked the members of the U.S. Armed Forces and appeared genuinely grateful that his band has been able to draw such good crowds and responses two decades after their inception.

Def Leppard took the stage at about 9 p.m. and made the questionable decision to open with a song most were unfamiliar with, "Undefeated," from their 2011 album "Mirrorball." Only the die-hards in the crowd seemed overly excited, but the band got itself together with "Rocket" from the 20-million-selling album "Hysteria."

Def Leppard has never been known for its poignant or thought-provoking lyrics, but their strong harmonies and unmistakable melodies created by studio master Mutt Lange propelled them into the sales chart and MTV playlist stratosphere. Those melodies and harmonies were on impressive display Saturday night.

Lead singer Joe Elliott mostly did his part more than admirably, hitting the familiar high notes where most of the singing audience could not on songs like "Women," "Animal," and "Bringing on the Heartbreak." Perhaps his most remarkable feat was performing the entire hour-and-a-half set in a black jacket during a sweltering Houston summer night.

The six-song acoustic medley was unique, featuring a blend of covers "You Can't Always Get What You Want," and well-known ballads like "Two Steps."

The closing numbers were proof that Def Leppard was no joke in their heyday. Few bands today can rely on a string of titanic hits to close out a show like "Hysteria," "Armageddon It," "Photograph," and the penultimate guilty please, "Pour Some Sugar On Me."

The night closed with a one-song encore, "Rock of Ages," which sounded exactly like its title: an aging rock band rocking harder than it has in ages.