Exclusive: Watch Julie Andrews Reveal Her Least Favorite 'Sound of Music' Song

"The Untold Story of The Sound of Music" Julie Andrews
Ida Mae Astute/ABC via Getty Images

To celebrate the 50th Anniversary of the classic film "The Sound of Music," Diane Sawyer tours Salzburg, Austria, and the surrounding Alps, with its star Julie Andrews, revisiting many of the actual locations and reflecting back on the most successful movie musical of all time for "The Untold Story of The Sound of Music." Andrews and Sawyer at the historic Mirabell Gardens in Austria.

While she has plenty of fond memories, Julie Andrews doesn't love every song from The Sound of Music. 

In the below clip -- which is an extra from tonight's 50th anniversary Sound of Music special on ABC -- Andrews shares with Diane Sawyer that there was one particular Sound of Music tune she didn't really care for: Her number "I Have Confidence," which was added for the movie and wasn't part of the original Broadway show.

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"The lyrics were a bit inane," Andrews explained. "Actually what I did, because I couldn't make sense of it and I have to have lyrics that make sense, I decided the best way to sing 'I Have Confidence' was to go completely nuts with panic and fear and busy work."

The Untold Story of 'The Sound of Music' airs tonight (Wednesday, March 18) on ABC at 10 p.m. ET.