ER fans know Jorja Fox as Dr. Maggie Doyle. West Wingers may remember her as Secret Service agent Gina Toscano, who saved the life of the president (Martin Sheen) last season. Currently, she’s co-starring in CBS’s surprise hit series CSI: Crime Scene Investigation. But even though she’s appeared on three of the hottest shows on television, Jorja Fox is not exactly a household name.

“I do like to keep a lower profile,” says Fox, 31, who plays forensic investigator Sara Sidel on CSI. “It’s been really fine for me to just sort of take things slowly and stay working.”

On the show, about a team of Las Vegas crime-scene analysts, Fox plays a hard-edged pragmatist who doesn’t flinch at the sight of a mutilated corpse. In one episode, for example, Sara takes notes for her boss Gil Grissom (William Petersen) at a bloody crime scene when a police officer becomes too queasy to handle the job. Though her alter ego has a strong stomach, Fox most certainly doesn’t.

“No. I am the wimp of the cast,” she admits. “And I think I was the wimp of the cast over at ER, too.” Fox played Dr. Maggie Doyle, whom she fondly refers to as “a vegetarian, gun-toting lesbian,” on the hospital series from 1996 to 1999. “There were several days on ER where I was nauseous for the duration of the scene.”

Apparently, the mood on the set of CSI’s morgue is so jovial that Fox doesn’t mind the phony blood and guts that much anymore. “It’s make-believe,” she says. “And we have so much fun on the set.”

Much of the “fun” is derived from Fox and her co-stars - Petersen, Marg Helgenberger, Gary Dourdan and George Eads - joking about the show’s gory special effects. According to Fox, a typical on-set quip would be, “Oh my God, look at that great bullet hole!” or “The morgue looks really nice today.”

Fox also enjoys herself when the cast flies to Vegas from L.A. to do location shots. “I’m not a big gambler, but there’s something really, really good about being in Las Vegas and having the excuse that you’re working to do all kinds of bad things. If you hit the slot machine with a gin and tonic in your hand, you can say, ‘Well, I’m working.’ "

The high-tech crime-solving methods employed by the CSI team on the show are nothing short of fascinating. So far, the team has found forensic clues in toenail clippings, blood, saliva and other icky substances either left at the crime scene or found in the dead victims themselves. In fact, would-be criminals watching the show may be deterred from committing illegal acts when they see how easily they can be caught by today’s technology.

But Fox has a flip side to that: Criminals could learn a few things from watching CSI as well, like how not to leave clues behind. “I think we’re going to have a lot of viewers from the prison system,” she jokes.

On a more serious note, Fox firmly believes in the ability of science to fight crime: “My good friend’s mom was murdered, and it was the scientific evidence that was able to conclude without any doubt that the person that they thought murdered her actually did. In fact, he’s in jail.”

Though the show is high on gore in its depictions of brutal crime scenes, it is low on actual violence. “It’s cool that we’re solving crimes without using guns,” says Fox. “I’m intrinsically antiviolent.”

Yet, as a crime-scene investigator, Sara does wield a pistol on CSI, as did Gina Toscano on The West Wing. “Yeah, and Maggie Doyle was really into guns,” adds Fox. “So I’m three-for-three on playing women who carry guns.”

Though she seems destined to play strong butt-kicking women on television, it is a fate Fox welcomes. “I’m lucky that I’ve been cast to play these really tough women. My God, if I’m going to be typecast, it couldn’t be better to be this type of chick. I love it.”