In 2001, Manning auditioned for the musical reality television show Popstar on the WB. In 2003, Manning and her brother Kellin formed the band Boomkat. The band first signed a major label deal with American Idol producer Randy Jackson, but the deal fell through. Robbie Robertson then signed them to DreamWorks Records, which was Boomkat's label from 2002 to 2004. In 2002, she sang a rendition of "I'll Take You There" with Tweet in several Gap commercials directed by Peter Lindbergh. Their debut album, "Boomkatalog.One", was released on March 18, 2003. Boomkat released two singles "The Wreckoning" and "What U Do 2 Me". The first single, "The Wreckoning", hit No. 1 on the Hot Dance Music/Club Play chart. The band closed out 2003 as the No. 5 Hot Dance Club Play Artist for the year in "Billboard Magazine". Music from "Boomkatalog.One" has also appeared in movies, including "Mean Girls", "Crossroads", "The Hot Chick", "8 Mile" and "The Italian Job".