Tierney Allen and Lady Gaga
Tierney Allen and Lady Gaga Image Credit: Social media/YouTube and AP

Washington DC: The eager spectators at a charity event in Las Vegas on Friday were easily fooled by Lady Gaga's impersonator.

The invitees of a national conference for Women of Global Change held at The Strat Hotel and Casino were shocked when they saw the pop-queen stroll onto the stage in a pink pantsuit and matching the wide-brim hat.

She then sat at a grand piano and belted out some of her biggest hits like 'You and I' and 'Million Reasons.'

According to The Hollywood Reporter, the interesting part was who the audience were actually watching was Tierney Allen, a Lady Gaga impersonator who performs regularly in Legends in Concert, a tribute review at The Tropicana that also features Freddie Mercury and Pat Benatar lookalike/soundalikes.

When contacted by The Hollywood Reporter, Allen says she had no intention of misleading the audience into thinking she was really Gaga.

"What happened is I was booked to perform at a private event for Women of Global Change. We always tell the clients to make sure the guests know I'm not the real thing," Allen said.

The confusion began when, at the end of her performance, the event moderator, Aurea McGarry, told the crowd that Allen was not an impersonator but was, in fact, the real thing.

"I thought, 'Oh, that's not good,'" recalled Allen. "I immediately started sweating. I must have looked like a deer in the headlights."

Allen has been mistaken for the artist before -- she was once surrounded by fans while visiting the Park MGM in full Gaga regalia while the "Poker Face" singer was performing there -- and decided to just "go with it" until she could get off the stage.