I had classical training but I don't consider myself an opera singer though.

Zajac. Debuting at the Sundance Film Festival the film won the Special Jury Award for Outstanding Ensemble Performance. In 2012 in addition to filming the third season of Shameless Rossum signed onto two film projects.

She currently stars on the Showtime dramedy Shameless as Fiona Gallagher. Her role in Mystic River (2003) garnered her wider recognition.