Rossum followed with various roles including a part in Clint Eastwood's acclaimed Mystic River, a lead in The Day After Tomorrow, and a Golden Globe-nominated performance for her turn as Christine in the movie adaptation of The Phantom of the Opera. Her voice was left relatively untouched during the editing process (unlike Gerard Butler’s) if you compare recordings of her live performances and of the movie soundtrack. In 2006, Rossum took to the studio to make a pop album with producers Glen Ballard, Stuart Brawley, and Moby titled Inside Out, Rossum's debut was released in October 2007 on Geffen. In 2009, Rossum began starring in the Showtime drama series Shameless.

In 2013, she delivered her sophomore album, Sentimental Journey, which featured a selection of standards from the '20s to the '60s. #Emmy rossum phantom of the opera movie#.Rossum also released three albums, Inside Out, the Christmas album Carol of the Bells and Sentimental Journey, writing many of her own songs. As Christine in The Phantom of the Opera, she sang such numbers as 'Think of Me' and 'All I Ask of You.' Rossum first sang as Deladis Slocumb in Songcatcher, notably performing the duet 'When Love is New' and also sang as the title character in Nola.

Rossum would also play the major character of Fiona Gallagher in Shameless and continued to appear in a number of major films, including Poseidon and Beautiful Creatures, as well as independent films such as Comet. She would come to global attention in 2004 after appearing in The Day After Tomorrow and The Phantom of the Opera. She soon appeared as Audrey Hepburn in a television biopic and made her film debut in 2000's Songcatcher. Born Emmanuelle Rossum in Manhattan, New York, she performed with the Metropolitan Opera Children's Chorus from the age of seven and began studying acting before making her television debut as Abigail Williams in As the World Turns.