Effie Passero and Shannon O'Hara, two American Idol hopefuls, duetted with country artist Cam during Monday night's (April 17) episode. Passero performed Cam's current single, "Diane," with her, while O'Hara and Cam collaborated on Cam's breakout hit, "Burning House."

Readers can press play above to watch Passero and Cam's rendition of "Diane." The two traded off lead vocals throughout the track and harmonized on the soaring chorus. After her performance, Passero revealed to the Idol judges -- which include Luke Bryan -- that she learned the song in 15 minutes.

Below, readers can watch Cam and O'Hara's rendition of "Burning House. Bryan called their performance "mesmerizing."

"She's so good," Cam said of O'Hara after their duet. "She's just so present, and she has so much going on ..."

Cam's appearance on Idol was part of a series of celebrity duet pairings with the show's Top 24 contestants. In addition to solo performances, the duets helped narrow down the field of hopefuls to 14; unfortunately (spoiler alert!), neither O'Hara nor Passero advanced.

Twelve of American Idol's Top 24 contestants competed for their spots in the Top 14 last week (April 8 and 9). Country duo Sugarland were among the celebrities to help out with duets then.

American Idol began its 16th season in mid-March. This season is the show's first on ABC, after running on Fox for 15 seasons.

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