It was a routine traffic stop, and as Marc Grayson approached the vehicle, he quickly asked the driver for her license and registration. Then, an agitated passenger started to berate Grayson, to question the police officer's authority. Voices grew louder, tensions rose.

In a flash, the woman at the wheel who had been searching for her license was holding a revolver, produced swiftly from an open purse. Her eyes were menacing, almost evil. Grayson, making a series of calculated decisions in less than a split second, literally weighing life and death, fired a single bullet into her chest.

As the lights flickered on and the screen went to an electronic blue, Grayson, a recruit at the Prince William County Criminal Justice Academy, put his gun down and let out a hefty sigh.

"That was very stressful," Grayson said, stepping away from the large computer screen. "They had my attention, they really did."

Though Grayson's bullets were nothing more than beams of light aimed at characters in a training video last week, his instructors hope that such realistic training will prepare Grayson and the rest of this year's recruit class for an often dangerous and intimidating job: protecting the county from the worst elements of society.

Last week, the 25 recruits training at the county's independent facility went through a series of tests and programs designed to hone their skills for real-life crime fighting. Their efforts come at a time when the community is taking an introspective look at crime and at those who are charged with preventing it.

Directors of the county's police academy say that the recent spate of violent crime--including four murders in less than nine days earlier this month--has not changed anything at the training facility, where every Prince William County police recruit since 1994 has learned the basics. If anything, instructors say, the violence has demonstrated the importance of rigorous and thorough training.

"The goal is to put them in a situation where they are doing what they will be doing every day," said Capt. Tim Rudy, who runs the academy. "It's high pressure, high stakes, and it can be quite dangerous."

The academy, in Nokesville along a stretch of farmland and rural homes, is one of a handful of independent training facilities across the state. It is designed specifically to train Prince William County police officers and members of the county's Fire and Rescue Department, along with sheriff's deputies and the occasional military officer. A facility that still looks and feels brand new, the academy also holds the county police firing range and a host of innovative training buildings, including a fire house and a three-story apartment building for simulated crime scenes.

Built earlier this decade, the academy was an alternative to sending the county's law enforcement hopefuls to regional academies. Instead, it allows instructors the flexibility of teaching specific methods and routines that apply only to Prince William.

First Sgt. Mike Crosbie, the academy's supervisor of basic training, said having a training facility in the county is "invaluable," saving time and money for a department that used to send recruits for generic training elsewhere only to have to retrain them for county-specific issues.

"Clearly this has been a much better way to train recruits because we can teach policies and procedures that are specific to our department," Crosbie said. "They are ready to go when they get out on the street."

Recruits spend slightly more than three months at the training academy before beginning several months of field training with officers on duty. A hire probably would not be on the street until 12 months on the job. Many of the recruits are just out of college, but some come from other jurisdictions--New York and Florida, for example--and need to go through the academy as a primer for duty in Prince William.

Rudy, supervising a few exercises and testing sequences Thursday, said the academy prides itself on its high priority for realism; police recruits are thrown directly into mock crime scenes, high-risk vehicle stops, even burning buildings to acclimate them to the wide variety of situations they might encounter on the job. After watching Grayson's CineTronic exercises with the interactive video, Rudy said the next step is virtual reality.

Dan Hess, 32, an instructor at the academy, said that although the academy often doesn't get much public attention, it plays a vital role in the department, ensuring that every officer has the same background and foundation when heading into the community. Hess, who has been teaching at the academy for more than two years, said the instructors understand their roles.

"We know that this is extremely important," Hess said. "We have a direct influence on what our department's going to look like in the future, and we all take that very seriously. Without a strong foundation, they would not be ready to go out into the field."

Halfway through his training, Michael Bradley, 28, of Fairfax County, was sent into a building Thursday to handle a fictitious crime scene. After walking up three flights of graffiti-laden stairs, he talked with a victim who said his computer had been stolen while he was away on business.

Bradley, expected to flawlessly run through a property crime scene, then dusted for fingerprints and carefully lifted evidence from a soda can--the lone mysterious element possibly left behind by the thief. Bradley's instructor said the recruit's performance was good, and passing, but he said Bradley could have delved deeper with his questions about the suspect.

"This type of training really helps out a lot," Bradley said, preparing for the inevitable batch of paperwork he was about to run through. "Running through it helps us tie all of the information together. It gets better with repetition, and we'll be ready when we need to be."

CAPTION: Officer in training James Lopez arrests classmate Charles Shanta while practicing a traffic stop at the county's police academy.