Though McPhee sang and acted throughout her childhood and high-school years, she began taking singing more seriously in college, attending Boston Conservatory as a musical theater major. After three semesters, however, she left for Los Angeles to audition for film and television work. McPhee scored roles in the film Crazy, a musical about Hank Garland, and an MTV series, You Are Here, which didn't make it to the air. She also appeared in productions of Annie Get Your Gun and The Ghost and Mrs. Muir before auditioning for American Idol in 2005.
Once McPhee made the final 12, her performances of songs such as "Someone to Watch Over Me," "Come Rain or Come Shine," and "Black Horse and the Cherry Tree" made her one of the favorites of American Idol judges and viewers. After the American Idol season ended, McPhee was signed by show creator Simon Fuller's 19 Recordings Limited label and released her first single, Somewhere Over the Rainbow/My Destiny; it became the second best-selling single of 2006.
That summer, after bouts with bronchitis and laryngitis, she joined the rest of the finalists and Hicks on the American Idols LIVE! tour and also toured with Andrea Bocelli, who appeared on American Idol as a guest judge. McPhee began recording her self-titled debut album in the fall, working with collaborators such as Timbaland's production partner, Nate "Danja Hand" Hills, Chad Hugo of the Neptunes, and songwriter Kara DioGuardi. "Over It," which was written by the songwriting team of Billy Steinberg, Josh Alexander, and Ruth-Anne Cunningham, arrived a few weeks before Katharine McPhee was released in early 2007.
