Marg Helgenberger
Mary Marg Helgenberger (born November 16, 1958) is an American actress. She began her career in the early 1980s and first came to attention for playing the role of Siobhan Ryan on the daytime soap opera Ryan's Hope from 1982 to 1986. She is best known for her role as Catherine Willows in the CBS police procedural drama CSI: Crime Scene Investigation (2000–13) and the subsequent TV movie Immortality (2015). She reprised the role in the sequel CSI: Vegas (2022–present). Helgenberger is also known for playing the role of K.C. Koloski in the ABC drama China Beach (1988–91), which earned her the 1990 Emmy Award for Outstanding Supporting Actress in a Drama Series. She is also known for roles in the TV series Under the Dome and Intelligence, and the films Species (1995), Species II (1998), Erin Brockovich (2000), and Mr. Brooks (2007). Description above from the Wikipedia article Marg Helgenberger, licensed under CC-BY-SA, full list of contributors on Wikipedia.
Movies
Fire Down Below
1997
as Sarah Kellogg
Jay and Silent Bob Strike Back
2001
as KC Koloski
Species II
1998
as Dr. Laura Baker
Erin Brockovich
2000
as Donna Jensen
Species
1995
as Dr. Laura Baker
In Good Company
2004
as Ann
Mr. Brooks
2007
as Emma Brooks
Bad Boys
1995
as Alison Sinclair
Always
1989
as Rachel