This post contains spoilers from the latest episode of The Masked Singer.
Harp kicked off the Thanksgiving episode by sharing who she feels grateful for: her mom.
"My mom and myself are very alike," Harp said in her clue package. "She was a singer just like me. She's like my rock."
The package also showed a #1 trophy. "If I had a handful of people the way that my mom believes in me, I know that I could soar so far because that woman thinks I can do anything," Harp continued. "And I want to win this for her."
Harp brought the energy with Lizzo's "About Damn Time."
"You could sing the phonebook and make me cry with a voice like that," McCarthy, 50, said. Scherzinger, 44, deemed it "the best performance of the entire season."
For an additional clue, a turkey brought out a picture of Oprah Winfrey.
"So, when I met Oprah for the first time, I brought my mom with me and was going to introduce her," Harp recalled. "But before I did, she said 'hello' and already knew her name. You know you've made it when Oprah knows your name and your mom's name."
Snowstorm brushed up on stage next.
"I always dreamed of being a pop star," Snowstorm said in her clue package that featured a movie ticket and a "LIVE" sign. "When I was in high school, I was taking voice lessons and one day, my mom said she got a call from my voice teacher saying, 'I'm sorry but your daughter doesn't have 'it.'"
Snowstorm dedicated her somber performance of Katy Perry's "Thinking of You" to her voice teacher. "Proving you wrong one day has kept me going all these years," she said.
Thicke, 45, called the Perry cover Snowstorm's "best vocal performance."
"Squiggly Monster was a dear friend of mine and is no longer with us," Snowstorm said. "And it feels really weird to cry with this voice, but he was the reason that I decided to do the show. Because his experience was just so rewarding and I'm so glad he got to have it before he passed away. My performances have been for him, whether he would want that or not."
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Lambs followed up by discussing how thankful they feel to be singing alongside one another again.
The white fluffy prairie animals talked about hitting it big in their younger years. "And even though we're incredibly grateful, we were so burnt out that we started to have issues" one of the Lambs explained. "And it was just very sad."
A "platinum class" boarding bass and a "forever friends" book popped up in the clue package as well.
"When we reunited it was like no time had passed," another Lamb said.
The trio hoped to win The Masked Singer because "we have won a few other awards in our lives, but it's been a very, very long time," one said.
Lambs sang Lady A's "Need You Now," which Jeong, 53, found to be "the most authentic performance of the evening."
Their additional clue: the word "reunion."
"For a long time, I didn't think that we would be singing together on a stage ever again," the Lamb dressed in pink said. "But I never gave up on the three of us getting back together and it's unthinkable of us not to be signing together again for the rest of our lives."
Once each act performed solo, they went up against one another in a three-way Battle Royale, putting their spin on Kelly Clarkson's "Since U Been Gone." Snowstorm rocked out with it, Harp offered up a sultry rendition and Lambs countryfied the hit.
The panel and studio audience voted for their favorite performer and as a result, host Nick Cannon announced Harp and Lambs would be the moving onto the finals. That left Snowstorm to unmask, and McCarthy's guess of comedian Glaser turned out to be correct. The Welcome Home Nikki Glaser star, 38, appeared under the sparkly flakes.
Jamie McCarthy/Getty; Michael Becker/FOX
"It was the first dream I ever had in wanting to be a performer," Glaser said of why she came on the show. "And it was squashed at such a young age and it just became something that was not attainable to me. So when this opportunity came up it was so perfect."
The FBoy Island host hopes to continue making music beyond The Masked Singer.
"This show really allowed me to forget all of the insecurities I had around singing and really explore my voice," she said. "And it's something I'm so excited to keep doing after this."
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The Masked Singer airs Wednesdays at 8 p.m. ET on Fox.