Traditionally, when producers of American Idol give contestants an enormous body of work from which to choose their songs—as they did this week by presenting them the entire Rock and Roll Hall of Fame songbook—many choose poorly. Over the last seven seasons, the AI faithful have watched contestant after contestant be told that their choice of song was wrong, either too high a register or too low, too iconic or too little-known. Luckily, on last night's Idol only one of the remaining four singers, dreadlocked Jason Castro, truly floundered in this area. That's not to say all of the Idols escaped unscathed, but Castro was clearly out of his element and should be going home tonight if there is any sense of musical justice on this show at all.

The other contestants managed pretty well ...

Leading off with the curious first song of Duran Duran's "Hungry Like the Wolf" (remember: entire Rock and Roll Hall of Fame to choose from here!) was rocker David Cook. Saying he gravitated toward the song because he thought he could add his own spin to it, Cook was entirely underwhelming. The judges, Randy Jackson, Paula Abdul, and Simon Cowell, were neither impressed or offended. Cook returned to form on his second song, "Baba O'Reilly" by The Who, and both Jackson and Cowell welcomed him. It should be noted that Abdul was "humbled to be here and watch [Cook's] soul."

Second in line was Syesha Mercado who sang, by her count, the 101st cover of Tina Turner's "Proud Mary." Though Jackson and Abdul liked it, Cowell called it "bad" and "shrieky." In an emotionally charged second song, she came out guns blazing on "A Change is Gonna Come," by Sam Cooke. Ending on a huge power note, Mercado looked absolutely crushed when Jackson said he "did not love it," and that she tried to make the song "something it wasn't." Holding back tears as Abdul gave her a standing ovation, she let them go in earnest when Cowell, in a rare gesture, agreed with Abdul. Mercado might garner the second lowest vote tally this week, but only because the competition is getting so close.

Sandwiched unfortunately between Mercado's power vocals and odds-on favorite David Archuleta was poor Castro. Castro's first song, a "rendition" of the Bob Marley classic "I Shot the Sheriff" was so profoundly awful, one had to wonder if it was an act of of self-sabotage. Needless to say, all three judges panned it. For his second song, Castro switched Bobs and did his best on Bob Dylan's "Mr. Tambourine Man." Confidence shaken, he flubbed his lines but got through the song. Cowell suggested Castro "pack his suitcase." If Internet rumors are true, Castro shouldn't mind at all.

The only contestant to earn all three judges' praise on both songs was David Archuleta. Perhaps almost impossibly earnest—finally host Ryan Seacrest acknowledged that Archuleta always looks like he's going to pass out before he receives comments from the judges—Archuleta sang "Stand by Me" by Ben E. King and turned Elvis Presley's "Love Me Tender" into ballad worthy of today's radio. Cowell said it best, telling Archuleta, "You didn't just beat the competition tonight ... you crushed the competition."