Marg Helgenberger is an American Emmy winner and Golden Globe-nominated film and television actress. She was born in Fremont, Nebraska, the daughter of Kay, a nurse, and Hugh Helgenberger, a meat inspector. She is of Irish and German descent and had a Catholic upbringing. Helgenberger played the French horn in her high school (North Bend Central High School) marching band. She attended Kearney State College (now the University of Nebraska at Kearney) in Kearney, Neb., then attended Northwestern Alumnus School of Speech in Evanston, Illinois (now the School of Communications) and earned a B.S degree in Speech and Drama.

Originally planning to be a nurse, like her mother, Helgenberger got her start as a nightly local news weather girl in her hometown Nebraska (her name was changed by the producer to Margi McCarty) and as a meat boner at the meat packing plant her father was working at during the day. After portraying the role of Blanche Dubois in a university production of “A Streetcar Named Desire,” she was bitten by the acting bug.

While performing in a summer of 1981 NU campus productions of Shakespeare's “Taming of the Shrew,” in which she played Kate, Marg was spotted by a scout for the TV show “Ryan's Hope.” Soon after completing college, Marg landed her first professional acting role on the long-running soap opera, playing uptight amateur cop Siobhan Ryan Novak (1982-1986), a role previously played by Sarah Felder and Ann Gillespie. Helgenberger is arguably the one most identified with the part.

Helgenberger departed Ryan's Hope in January 1986 and guest starred in an episode of ABC's mystery/detective series based on Robert B. Parker's "Spenser" novels, "Spenser: For Hire," NBC's legal drama "Matlock" and ABC's ground-breaking, award-winning drama "Thirty Something." She also played a regular role as Natalie Thayer, opposite Margot Kidder and James Reid, on CBS’ six-episode drama comedy series "Shell Game" (1987).

Karen Charlene "K.C." Koloski, a heroin addicted prostitute on the ABC war drama series "China Beach," was Marg’s first prominent role. Her performance from 1988 to 1991 on the highly-acclaimed dramatic series won an Emmy Award for Outstanding Supporting Actress in a Drama Series in 1990.

Meanwhile, in 1989, Marg made her feature film debut in a leading role as an all-night answering service operator in one segment of the Wheat brothers’ horror anthology After Midnight. She followed it up with a role in Steven Spielberg's romantic comedy-drama Always (starring Richard Dreyfuss, Holly Hunter, and John Goodman), a modern version of the original 1943 Victor Fleming film A Guy Named Joe.

During the early to mid 1990s, Marg played roles in Michael Bortman's adaptation of Robert Boswell's novel, Crooked Hearts (1991; with Peter Berg, Vincent D'Onofrio, Jennifer Jason Leigh Noah Wyle and Peter Coyote), Gregg Champion's action comedy The Cowboy Way (1994), in which she played Woody Harrelson's love interest, and had a small role as Capt. Alison Sinclair in Michael Bay's action comedy film starring Martin Lawrence and Will Smith, Bad Boys (1995). She also played Dr. Laura Baker, a molecular biologist, in Roger Donaldson's sci-fi thriller starring Natasha Henstridge Species (1995), and later reprised the role in the sequel, Species II (1998).

During that time, TV viewers could also catch her in such television films Blind Vengeance, Death Dreams, PBS’ historical documentary Not on the Frontline (as a narrator) and CBS’ In Sickness and in Health. Additionally, she was also seen opposite Bruno Kirby in I'll Be Waiting, a segment of Showtime's Fallen Angels helmed by Tom Hanks, and as a novelist on the ABC miniseries Stephen King's The Tommyknockers opposite Jimmy Smits. She was also seen in the CBS miniseries When Love Kills: The Seduction of John Hearn and made her first collaboration with director Peter Weller in Showtime's Partners. After playing a recurring role as George Clooney's love interest on NBC's popular medical drama ER, Marg became David Caruso's sex-starved widow on Showtime’s Elmore Leonard's Gold Coast, helmed by Weller, and starred as a woman involved with Steven Segal in the 1997 cult action film Fire Down Below. She also starred opposite Ann-Margret in Showtime's Happy Face Murders.

Helgenberger scored another big break when she snagged the co-starring role of Catherine Willows, a former show girl employed as a blood spatter analyst on the popular Emmy Award-winning CBS drama CSI: Crime Scene Investigation. Her performance as the female lead has earned her two Emmy Award and two Golden Globe nominations. In 2005, she and her fellow cast members won the Screen Actors Guild Award for Outstanding Performance by an Ensemble in a Drama Series.

During her hefty stint on the hit show, Marg supported Julia Robertsin the true story-based, Oscar-winning film Erin Brockovich and portrayed Patsy Ramsey in the CBS miniseries about the mysterious murder of 6-year-old beauty pageant contestant JonBenét Ramsey in Perfect Murder, Perfect Town. She also starred as Dennis Quaid’s wife and Scarlett Johansson’s mother in writer-director Paul Weitz's romantic drama comedy In Good Company (2004) and appeared on Pond's Smooth Perfection Skin Cream 2005 print ad.

Recently, on June 1, 2007, Marg's latest film, Mr. Brooks, was released. In the gripping suspense thriller directed by Bruce A. Evans, she co-stars as the beautiful, loving wife to Kevin Costner Demi Moore William Hurt and Dane Cookalso star in the film.

In 2005, Universal Studios submitted Helgenberger in the best supporting actress category for the Oscars for her performance as Ann Foreman in her 2004 movie In Good Company.