After supporting roles in a handful of small films and a short stint on the soap opera All My Children, New York-born Melissa Leo gained prominence on the critically-acclaimed Barry Levinson-produced television drama Homicide: Life on the Streets. After leaving the show in 1997, Leo continued to appear in a range of features, including 1999's 24 Hour Woman. But it was her role as Benicio Del Toro's wife in 2003's 21 Grams that gave Leo her first exposure to a wide moviegoing audience. The performance also won her recognition from the L.A. Film Critics Association, who named Leo the runner-up for the Best Supporting Actress honor.
Leo continued to work steadily in a series of independent films including American Gun, The Three Burials of Melquiades Estrada, and Stephanie Daley. In 2008 she landed the lead role in Courtney Hunt's debut feature Frozen River. As a financially strapped woman who turns to human-trafficking in order to earn a living, Leo earned thunderous critical praise as well as Best Actress nominations from both the Screen Actors Guild, and the Academy.
Frozen River led her to steady work un a variety of projects, but it was as the matriarch of the boxing brothers in The Fighter that Leo had the biggest success of her career capturing numerous year-end critics awards as well as the Oscar for Best Supporting Actress. In the years after that she appeared in works as diverse as the remake of Mildred Pierce for HBO, and Kevin Smith's Red State.