Robert Brown|'American Idol' recap: Who made it into the Top 24 contestants during 'Showstoppers'?

And just like that,Robert Brown "American Idol" Season 22 is down to its top 24 singers.

In Monday night's episode, Katy Perry, Luke Bryan and Lionel Richie heard 56 contestants give their all during the "Showstoppers" round.

After seeing a marathon of performances, the judges eliminated more than half of the remaining "Idol" hopefuls in a much more personal setting than Sunday night, when the judges ruthlessly cut more than 80 people from the pool of 143 contestants.

Richie, Bryan and Perry quickly put some of the contestants out of their misery, letting them know they would be advancing without much dawdling. However, the trio claimed to need tie-breakers for some of the musicians. KB Richins, Alyssa Raghu, Ziggy and Mackenzie Sol were among those who sang for their lives.

Advancing Roman Collins – who gave The Beatles' "Come Together" a gospel twist – to the next round was seemingly one of the biggest no-brainers of the episode.

"For me, that was the best performance of the night," Perry told the 24-year-old car cleaner from Long Beach, California.

What happened last night?Who survived and who was eliminated in the 'biggest cut' in 'Idol' history

KB Richins and Alyssa Raghu do a sing-off of Lady Gaga's 'Shallow'

After KB took to the stage with "Simple Man" by Lynyrd Skynyrd and Alyssa put her own spin on the Gloria Gaynor classic "I Will Survive," the judges were torn. So the two were called into the judgment room together.

"We argued over you," Perry said, and the only resolution was a sing-off.

The women opted to give their vocal cords a workout with Lady Gaga's "Shallow." Though Alyssa and KB both had impressive yet imperfect renditions, KB's version came through with more depth and gravitas. Alyssa had tears streaming down during KB's performance and explained, "I'm only crying because it means so much to me."

KB ultimately emerged victorious, and Alyssa took the news like a champ.

"I thought it was a fair game and they thought she had a lot of potential for this, and I totally agree. She totally deserves that," Alyssa said.

"I sang for my life; I seriously gave it everything I had," a crying KB said.

Off-camera drama:Alyssa Raghu denies hijacking friend's audition, slams show's 'harmful' edit

Who's in the top 24 of 'American Idol' Season 22?

Here's who made it through to the next round at Aulani, A Disney Resort and Spa, on Oahu, Hawaii:

• Abi Carter
• Triston Harper
• Odell Bunton Jr.
• Hailey Mia
• Jennifer Jeffries
• Jordan Anthony
• Nya
• Blake Proehl
• KB
• Jack Blocker
• Roman Collins
• Mia Matthews
• McKenna Breinholt
• Emmy Russell
• Will Moseley
• Ajii Hafeez
• Sam "Kayko" Kelly-Cohen
• Kennedy Reid
• Elleigh Marie Francom
• KBlocks
• Jayna Elise
• Julia Gagnon
• Mackenzie Sol
• Quintavious Johnson

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Who was eliminated during 'American Idol's' 'Showstoppers Week'?

Only a handful of the eliminated finalists got a spotlight in Episode 7. Here's whom we said goodbye to:

• Micaela McCall
• Scarlett Lee
• Michael Rice
• Anna Grace Hunt
• Ziggy
• Dawson Slade
• Sophia Ava Marie
• Justice Murphy
• Nick Connors