Most of Alice Cooper's act, once thought menacing, is strictly for giggles now. But at Wolf Trap on Thursday, Cooper had everybody laughing along with him.

Cooper brought out all the props that he used during his "Welcome to My Nightmare" days of the early '70s, when he was among the biggest concert attractions on the planet -- the Wolf Trap stage probably never hosted a casket, a whip, a live snake and a guillotine on the same night before.

Yet for such a veteran, Cooper had some pacing problems. He front-loaded the set with his heaviest hitters -- "No More Mr. Nice Guy," "I'm Eighteen" and "School's Out." Backed by a youngish hard-rock foursome, Cooper acted as if he still likes what he does. But none of the relatively fresh material Cooper performed in the last third of his show could stand up to his oldies. The best of the newer tunes was 1994's "Lost in America," which had Cooper singing, "I can't go to school 'cause I don't have a gun." Now that's scary.

Cheap Trick, a perennial opening act that still features its original 1974 lineup, can be viewed as a rock-and-roll version of a plant worker in the band's native Rust Belt, the kind of guy who got a job after high school and kept showing up and giving it his all without ever getting the sort of recognition he deserved.

But if band members felt supporting Alice Cooper was unjust, they didn't let on. Rick Nielsen, one of the great guitar hoarders in rock history, still switches instruments about every song. For "Never Had a Lot to Lose," Nielsen stroked a double-necker that was shaped and painted like Rick Nielsen, goofy cap and all. Singer Robin Zander mocked the band's maturity while mentioning that they would play the MTV Music Awards, being held this weekend in Miami, if only anybody at the channel wanted them. "We were too old when they started," Zander said of the 25-year-old MTV.

Yet during "Surrender" Zander built up enough steam to nail the song's fabulous final "Awaaaaay!" in a way to raise hairs on every 45-year-old teenager in the building. Zander, without any obvious digital assistance, also delivered the chills while singing "The Flame," a 1988 power ballad that led some hard-core fans, back in the day, to blast the band for selling out. But all has been forgiven. On this night, the audience sang every sellout word.

Alice Cooper performed his biggest hits with panache; Cheap Trick, left, played an array of unconventional guitars.