Born in Atlanta on November 10, 1977, Murphy was raised by her mother in Edison, New Jersey. A precocious child who began putting on shows when she was a toddler, Murphy was acting in regional theatre productions by the age of nine. Work in various commercials followed, and in 1990 she landed her first television role, on the sitcom Blossom. She then went on to a lead on the short-lived sitcom Drexell's Class in 1991, and the following year she made her film debut in the dysfunctional family drama Family Prayers. Murphy's talent for portraying all sorts of dysfunction was further exhibited in such films as Clueless; the Reese Witherspoon trailer trash odyssey Freeway (1996); and the made-for-TV David and Lisa (1998). Murphy won particular acclaim for her work in the last film; the story of two emotionally troubled teens (Murphy and Lukas Haas) who reach out to each other allowed the actress to prove herself in a purely dramatic role. In 1999, Murphy could again be seen portraying an emotionally damaged character in Girl, Interrupted, in which she played a patient at a mental institution. That same year, she explored the collective insanity of the beauty pageant world in Drop Dead Gorgeous, playing a pageant contestant who'd rather be living it up in New York with her cross-dressing brother. On the small screen that year, she switched to much darker fare with the Holocaust drama The Devil's Arithmetic. With her plate increasingly full moving into the new millennium, Murphy could be seen in the both the Michael Douglas thriller Don't Say a Word, and alongside Drew Barrymore in Riding in Cars With Boys in 2001. Cast opposite Eminem in director Curtis Hanson's 2002 /drama 8 Mile, Murphy provided a compelling performance as an aspiring rap star's unapologetic muse before starting 2003 on a lighter note with the comedy Just Married.
In addition to the praise she has received for her film portrayals, Murphy has won a different sort of acclaim for the work she has done on the animated TV series King of the Hill. As the voice of the Hills' beauty school sex kitten niece Luanne, the actress earned the kind of recognition that can only come from an animated character who was named one of the sexiest women on television by a major men's magazine. ~ Rebecca Flint, All Movie Guide