Instead of doing two songs each as "Idol" has done in years past, each contender – Adam Lambert, Allison Iraheta, Kris Allen and spectacled Danny Gokey – performed one solo number and a duet with one of their fellow finalists.
Adam, who last week made his first trip to the bottom two, was up first, and after some help during practice from guest mentor Slash, he slayed the judges with a faithful rendition of Led Zeppelin classic, "Whole Lotta Love."
"This is the Adam that I love, dude. Let me tell you something right now — nobody is going to think about Broadway or any of that stuff. You're a rock star tonight," Randy Jackson raved. "I hope you consider, when making a record, you are a rock star waiting to happen… In fact, you and Slash should make a record… That was hot."
Adam had the only universally lauded solo performance, but both duets were received well by the judges.
Adam sang "Slow Ride" by Foghat with Allison and the two not only looked the part with their spiky highlighted hair, but they sounded it with their dueling yet complimentary rock n' roll vocal runs.
"You guys are our two seasoned rock stars in the house and I'm telling you guys, you should do a duet on your albums," Randy said. "That was the bomb, baby!"
Kris and Danny's duet was on "Renegade" by Styx, and that too received praise.
"I think this was really great to introduce this season – to have you doing duets," Paula Abdul stated. "It was powerful and it was compelling. Good job."
But Kris, Danny and Allison had fewer compliments for their solo songs.
Allison's version of Janis Joplin's "Cry Baby" left Randy disappointed.
"I didn't love it," he said. "This wasn't that great for me."
And though Kris put his own stamp on the Beatles classic, "Come Together," by trying out new runs and changing parts of the melody, it didn't sit well with Simon.
"I actually didn't like it that much," Simon complained. "It was rather like eating ice for lunch in like it will leave you with nothing to remember afterward. It was actually quite a boring song. It was a bit of a jam."
Danny didn't fare much better. In fact, his rendition of Aerosmith's "Dream On" left the panel with mixed impressions.
"I know this was a tricky genre or you," Paula said. "I don't know if this was the right song for you, but I'm a huge fan of yours… I give you an A++ for going for it."
But Simon slammed Danny – the only contestant remaining who has failed to appear in the bottom three all season long.
"The last note – it was like watching a horror movie… It was like 'Friday The 13th.' It was like this scream," Simon said. "It was actually a little bit over the top…. But, I still think you're gonna be safe tonight."
And there was drama beyond the contestants too.
Host Ryan Seacrest revealed at the start of the show that there had been an accident on the stage earlier in the evening and one of the towers that holds up the "American Idol" logos on either side of the stage came unhinged just before dress rehearsal.
"Glass was popping everywhere," Ryan said. "So the contestant have not had a proper run through to the show. But as they say in Hollywood, the show must go on."
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