There were no sharks, shooting stars or faux lions performing with Katy Perry Sunday night in St. Paul in her only U.S. performance of 2015 other than the Super Bowl, where she worked with all those props and a cast of thousands.

For the Starkey Hearing Foundation's 15th annual So the World May Hear gala Sunday, it was just Perry with her five musicians and two backup singers (all dressed in white to match her grand piano). Before she sang a note, the 30-year-old pop princess talked about how inspired she was by the work of Starkey that she'd heard about for the previous four hours.

Frankly, once she began singing, Perry seemed as stiff as her voluminous gown, as tired as an overbooked globe-trotting superstar, as uninspired as a candidate who knows she's dropping out of the presidential race tomorrow.

Perry is the hottest booking in the history of the Starkey galas. Usually the hearing-aid organization turns to classic names for headliners — Garth Brooks, John Mellencamp and Elton John (twice). But maybe Miss Teenage Dream was too cool for the room filled with gowns and tuxedos whose kids might have wanted to witness this pop queen live.

For whatever reason, Perry gave a quickie cameo — a five-song, 24-minute performance. Sir Elton played his songs for 50 minutes one year and a full hour another time. Even has-been Sammy Hagar rocked the house and shattered eardrums for 30 minutes last year.

Perry opened with the most lifeless "Roar" you've ever heard. She pounded her chest during "Part of Me" and brought a few folks to their feet for "Teenage Dream." She introduced "Unconditionally" by talking about tolerance and how the Starkey folks and attendees give their love unconditionally. She injected a modicum of passion into the ballad.

"Firework" was a fitting finale but it was more fizzle than ooh-aah. "C'mon sing it," she implored the crowd. And the gala-goers didn't really respond vociferously.

Other performers ignited the 1,600 ballroom patrons. You want the best? Then call Kiss. Or at least one of its members.

Kiss bassist Gene Simmons rattled the RiverCentre roof by performing "Rock 'n' Roll All Nite," accompanied by a choir of Edina High School students and a bald drummer wearing a tie, the Twin Cities' own Joe Pulice. Always ready to rock, the makeup-free Simmons took off his dark suit coat to perform in an open-collar black dress shirt (no tie of any kind for Mr. Kiss).

In mid-song, Simmons even shed his shades to put them on Twin Cities guitarist Cory Wong as he shredded on a solo. Fun can come without expensive props.

Simmons didn't just carry on like a rock star, he put his money where his rock-star mouth is by ponying up $250,000 for a Starkey mission to China — the first live auction of the night. More than $9 million was raised Sunday, a record for a Starkey gala.

But perhaps the real rock stars of the evening answer to No. 42 and 43 — former presidents Bill Clinton and George W. Bush. The latter received an award and showed off his humor. He said Simmons told him that Kiss stood for "keep it short stupid." Bush said he wasn't well-versed on the Borscht Circuit comedians, so he Googled Starkey emcee Norm Crosby, who was billed as the master of malaprops, and added, "They should have mentioned George W. Bush's language teacher."

Clinton spoke later and longer than Bush but he got off a few zingers, too. He had been introduced as possibly the next First Lady, to which he said "I'm not trying to compete with Ms. [Caitlyn] Jenner." He also pointed out that one of Perry's representatives had worked for him "before [the man] got a promotion."

Clinton, who has gone on six Starkey hearing-aid missions, did get serious, too. Speaking before Perry closed the program, he said he felt like a Southern minister giving a prayer at the end of the service when people come down the center aisle.

"You may not go to hell if you don't come down the Starkey aisle," the former president said, "but you'll certainly go to heaven if you do."