"Clueless" propelled the actress into a different realm. As the dumpy Easterner Tai, Murphy proved her comic mettle and began to get roles in independent films, many of which debuted on premium cable channels like HBO (i.e., "Freeway" 1996, "Phoenix" 1998). Returning to NYC, she won her fair share of critical praise as the niece of a dockworker (Anthony LaPaglia) who has more than avuncular interests in her in the acclaimed, award-winning 1997 Broadway revival of Arthur Miller's "A View From the Bridge". Murphy's profile rose higher when she was tapped to co-star opposite Lukas Haas in the small remake of "David and Lisa" (ABC, 1998), produced under the "Oprah Winfrey Presents" banner. She then co-starred as one of the pageant aspirants in the mock documentary "Drop Dead Gorgeous" (1999).

As a suicidal teen fixated on rotisserie chicken in "Girl, Interrupted", Murphy gave a highly memorable performance, which she followed up with skilled performances as vastly different characters, counting among her 2000 credits a turn as a discharged naval officer suspected of being a lesbian in the 1950s-set segment of Showtime drama "Common Ground", a performance as a charming barfly in the independent "Trixie" and a virginal girl targeted by a serial killer in the teen slasher pic "Cherry Falls". Her supporting role as the loveable town floozy in "Summer Catch" (2001) was one of the disappointing film's few high points, while she held her own in a challenging turn as a disturbed young woman who holds a valuable secret in her damaged mind in the thriller "Don't Say a Word" that same year. Her performance--and her memorable "I'll never tell" line featured in the film's ad campaign--finally seemed to make Murphy a recognizable star. She also excelled with a featured role as a waitress in the ensemble of the Edward Burns romantic comedy "Sidewalks of New York" paired Murphy with Stanley Tucci and David Krumholtz and perfectly complemented Drew Barrymore in the inspiring fact-based comedy-drama "Riding in Cars With Boys" (both 2001).

Though her starring role in the proposed Gary Fleder-directed Janis Joplin biopic was shelved due to music rights difficulties, Murphy recovered with a role in the romantic comedy "You Stupid Man", directed by Brian Burns (brother of Edward), a featured turn as a amphetamine addict paired with Mickey Rourke in the black comedy "Spun" directed by famed Madonna video helmer Jonas Ackerlund and Curtis Hanson's "8 Mile" (2002), which starred and was loosely based upon the life of successful white rapper Eminem (all lensed 2001). She then started the new year off by starring, with then-boyfriend Ashton Kutcher, in the romantic comedy feature "Just Married," which failed to capitalize on the couple's loopy real-life chemistry in favor of shrieking histrionics, and played on-screen the drug addicted girlfriend to Mickey Rourke's character in the independent feature "Spun" (both in 2003). That same year Murphy--whose image slowly changed from wild child character actress to sophisticated starlet--also tackled her first full-blown leading lady capacity in the light comedy "Uptown Girls," starring as a rock star's hard-partying, suddenly cash-strapped daughter who is forced to grow up when she becomes the caretacker of a wealthy, willfull and ignored little girl (Dakota Fanning). Murphy continued to land headliner roles, cast as the lead in the lightweight romantic comedy "Little Black Book" (2004) as a talk show producer who delves into her commitment-phobe boyfriend's Palm Pilot and makes some disturbing discoveries about his romantic past; the actress added an admirable, highly watchable spark to the otherwise leaden affair.

Next Murphy appeared as Shellie, the strip club waitress with a soft spot for the wrong guys, in director Robert Rodriguez and writer-artist Frank Miller's visually arresting adaptation of Miller's crime noir comic book series "Sin City" (2005). Murphy's character helped tie the various story arcs together by appearing in multiple sequences, most notably in "The Big Fat Kill" where her character is terrorized by the corrupt Jackie Boy (Benicio del Toro) before being saved by the tough but noble Dwight (Clive Owen).

Despite her onscreen capabilities, the actress' longest running and perhaps most widely appreciated work is her turn as the vocal talent behind aspiring beautician Luanne on the Fox animated series "King of the Hill" (1997- ). She also provided the voice of the fidgety greyhound Nellie in the kid flick "Good Boy!" (2003).