Usually, when an "American Idol" finalist makes a surge back into contention it's via a beloved pop or R&B song that they either smash or turn on its head in an unexpected way. But on Tuesday night Lee Dewyze took a lesser-known soul nugget, the Cornelius Brothers & Sister Rose's 1971 hit "Treat Her Like a Lady," and slathered it with his bar-rocker grit and a newfound confidence that wowed the judges.

With advice from guest mentor Usher to believe in himself, Dewyze let loose like never before for a performance that Randy Jackson called, simply, "unbelievable." The normally compliment-stingy Simon Cowell was even bowled over, telling a stunned Dewyze, "This was the night your life may have changed forever."

How did Lee turn things around? By picking an R&B classic from a Florida family act that was essentially a two-hit wonder, dissolving not long after hitting the top with "Lady." Songwriter Edward Cornelius, late brother Carter Cornelius and sister Rose Cornelius roared out of the gate with the chugging doo-wop soul tune from their self-titled debut, selling more than a million singles and hitting #3 on the pop charts.

Another sister, Billie Jo, joined in 1972, just in time for their second million-seller, "Too Late to Turn Back Now," which hit #2 on the pop charts and marked the last time the group would make any significant chart impact. The group broke up in 1976, after Carter joined the black Hebrew religious cult Nation of Yahweh in Miami and adopted the new name Prince Gideon Israel. He would spend the next 15 years recording music for the cult led by Yahweh ben Yahweh before dying at age 43 of a heart attack in 1991.

According to his MySpace page, Edward became a born-again Christian in 1989 and began a second career a gospel music artist and pastor of the Blood of the Lamb ministries, while Rose continues to perform occasionally in Florida.

The group's songs continue to be popular oldies radio staples, and "Too Late to Turn Back Now" was used in a series of Office Depot commercials in 2001. "Treat Her Like a Lady" was prominently featured in the 2004 Will Ferrell comedy "Anchorman."

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