Kris Allen was nervous about disco night on "American Idol." The shy 23-year-old from Conway, Arkansas, has made a name on "Idol" with his measured, Jason Mraz-ish, blue-eyed-funk sound, but he said Tuesday that taking on a tune from the boogie-fever era made him a bit tense.

But borrowing a page from the trailblazing book of this year's leader of the "Idol" pack, Adam Lambert, Allen showed his versatility by turning Donna Summer's "She Works Hard for the Money" on its head and completely reinventing the song. Switching it up Santana-style, Allen strummed his acoustic guitar on a stripped-down arrangement in which he was joined by a pair of percussionists and an electric bass player for a salsa-fied take that was more John Mayer than John Travolta.

It was a fitting changeup for a tune from peerless disco queen Summer, who actually released the song long after the lights had faded on the dance movement. Having scored a string of indelible hits in the mid- to late 1970s ("Love to Love You Baby," "I Feel Love," "Last Dance"), "She Works Hard for the Money" was released in 1983 — it appears on the album of the same name — after a period in which Summer was experimenting with a more new-wave sound.

The Grammy-nominated song was a return to her dance roots, and it became a kind of feminist anthem, helping Summer notch her first-ever R&B #1 hit and paving the way for her to become one of the first black women to get a video in heavy rotation on MTV. Despite "Idol" host Ryan Seacrest's more salacious insinuation on Tuesday night, the tune was reportedly inspired by an experience Summer had in the famed Los Angeles restaurant Chasen's, where she saw the bathroom attendant, Onetta Johnson, taking a nap.

When Johnson was startled awake by Summer, she told the singer that she worked two jobs and was exhausted, inspiring Summer to scribble down the title phrase on a scrap of toilet paper and then write the song that night at home in about 20 minutes. Johnson's picture appeared on the back of the album, and she is given a shout-out in the lyrics: "Onetta there in the corner stand/ And wonders where she is, and it's strange to her/ Some people seem to have everything."

The tune was co-written by Armenian-American songwriter Michael Omartian, who produced the album and also co-produced "We Are the World" with Quincy Jones.

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