Girls Aloud by Louis Walsh until 2005 when Hilary Shaw replaced him. The new group competed with the boys' winning group, One True Voice to have 2002's Christmas number one single. Girls Aloud won the battle with their single "Sound of the Underground", produced by Brian Higgins and Xenomania. The song spent four consecutive weeks at number one and was certified platinum in March 2003. The song received critical acclaim; Alexis Petridis of "The Guardian" stated that "it proved a first: it was a reality pop record that didn't make you want to do physical harm to everyone involved in its manufacture".
Girls Aloud "The Guardian" labeled it "the best pop single of the last decade". The release was followed by a cover of Dee C. Lee's "See the Day", released in the Christmas week of 2005., following this they presented one-off TV Special, Christmas Mania, on ITV, where they sang songs taken from their Christmas album. Girls Aloud won the Heart Award for the single at the O Silver Clef Lunch. The group travelled to Australia and New Zealand in February 2006 to release "Biology" and "Chemistry". Despite, a one-week promotional tour, "Biology" peaked at number twenty-six on the ARIA Singles Chart, failing