Alicia Kozakiewicz, 13, feared she was about to be murdered. Abducted outside her Pittsburgh home by a 38-year-old man she met in a Yahoo chat room, she had been held hostage, tortured and sexually assaulted for four days in a weapon-filled dungeon. Leather collar around her neck, she had been chained to the floor. Mercifully, she can't recall most of the horrors she endured, but she does remember "it was the first time I ever really prayed," says Kozakiewicz, now 19. "I kept waiting for the cavalry to come."

Miraculously it did, in the form of a team of FBI agents, who burst into the Virginia townhouse and rescued her on Jan. 4, 2002. The big break in the case was a tip from a Florida man who had seen a video of Alicia made by her tormentor, who had boasted he had captured a teenager. The FBI eventually traced his screen name, provided by the tipster, to his townhouse.

Determined that what happened to her would not happen to others, Kozakiewicz began talking to groups of kids, warning them of the dangers of the Internet. Now a freshman at Point Park University in Pittsburgh, she gives her 45-minute presentation every Friday to local elementary or middle school students. Given the awful power of her tale, she's been inundated with requests to speak. "I admire what she's trying to do," says FBI special agent Denise Holtz, who spearheaded Kozakiewicz's case with now-retired U.S. postal inspector Tom Clinton. "But I worry about whether it's good for her to relive what happened."

Even Kozakiewicz isn't sure about that. But here she is, on a cold winter morning, speaking to some 400 seventh and eighth graders at Independence Middle School in Bethel Park, Pa. Projected behind her on a screen is her missing poster. "That's me about five years ago," she tells the kids, who listen with rapt attention. "I was almost just another body in the morgue. So please: Listen to me.... I was just an average 13-year-old girl."

By all accounts, including that of the FBI, she was. Her mother, Mary, stayed at home to raise Alicia and her older brother Chuck. Her father, Charlie, supported the family selling cars. They kept their computer in the family room to keep an eye on how much it was used but said they had no idea Alicia was going online after they went to bed. And they attributed any moodiness they saw to typical teenage angst. "We were definitely not aware there were any problems, or the computer would have gone out the window," says Mary, now 50. "We were very naive."

For Alicia, talking about what happened to her is still not easy. She's lost huge chunks of her memory, including most of her life prior to her abduction. Psychologists say such memory loss is not uncommon in the aftermath of deep trauma. "Victims may lose personal information, personal memories, past experiences," says Veronique Valliere, a psychologist who specializes in the treatment of sexual abuse. "Brain chemistry changes under huge stress."

Alicia recalls bits and pieces of how she came to meet Scott Tyree, her abductor, online. She said she'd been corresponding with a girl named Christine for months before discovering Christine was actually a 31-year-old man. She said she was mad for a few hours, then got back online with her friend because, in her mind, "Christine was still Christine to me," Kozakiewicz said. At some point "Christine" introduced her to Tyree in a Yahoo chat room. While authorities later said he advertised himself online as "Master Scott" and had dozens of pictures of himself and sexual instruments, including chains, whips, a cage and paddles, Kozakiewicz says she recalls none of that. During the six months they corresponded, he easily manipulated her. "He turned me into what he wanted," she says. "It's like he erased me." As she tells her audiences, "There are lots of predators on the Web. They are older than us. Smarter than us. If you give them any information, they'll get you." [See box]

She still doesn't remember why she left her house on New Year's Day, 2002, although she knows she and Tyree must have made arrangements for him to travel from Virginia and pick her up. What she does recall is that she got into his car outside her home. "The next thing I remember is being in the basement," she says. She was fed only once during the four days she was held hostage. She was chained in his bedroom around 4 p.m. on Friday, Jan. 4, while Tyree was at work, when help finally arrived. It wasn't until she saw the FBI lettering on the jackets of the people in the room that she realized she'd been rescued. "I didn't know if it was real at first," she said. (The Florida tipster who had seen Tyree's video of Alicia with her arms bound, hanging from the ceiling, had also seen news stories about Alicia being missing; he called the FBI.) Meanwhile, hundreds of miles away, Holtz, who had helped track down Tyree, and other agents in the Pittsburgh office were breathlessly waiting to hear back from their colleagues from the D.C. office, who were handling the rescue attempt because they were closer. "They called and said they found her and she was alive," Holtz said. "It was definitely one of the highlights of my career. It was amazing."

So too is the cautionary power of Alicia's tale. After one of her talks at Bethel Park, a few kids were visibly shaken and said they were going to take down their MySpace accounts. "I didn't think anything like this could really happen," said Alyssa McCuistion, 13. "But hearing things can happen to you, even if you're just an average teen, scared me." Kozakiewicz has received dozens of thank-you letters from teens who have seen her program. Several kids have broken off what they now realize were inappropriate Internet relationships.

When Alicia was first rescued, "she was a shell of herself," says her mom. She has been through counseling, but Alicia thinks she needs more. Her mom agrees: "I think she's made remarkable progress in that she's able to stand up and speak about these things, but she's going to carry an inner pain forever. I don't think you can survive that kind of terror and not be scarred."

To this day Kozakiewicz won't speak Tyree's name, even during the presentations, because if she does, she pictures his face. If the kids ask what happened to her abductor, she tells them he pleaded guilty and was sentenced to nearly 20 years in prison. Sometimes she can talk about what he did to her but sometimes she can't, saying, "If I do, I'll cry," as she did at one of the Bethel Park presentations. One of her few pre-abduction memories is of a family trip to Disney World. After her rescue, Kozakiewicz says, she became almost obsessed with Tinkerbell; her room is a virtual shrine to the Disney character. "It's the whole eternal youth thing," she says with a sad smile.

Perhaps it's no surprise then that Kozakiewicz is a psychology major. She still calls the agents who saved her on the anniversary of her rescue. She is participating in an FBI video about Internet safety and says she wants to join the FBI after she receives a master's degree in forensic psychology.

"I'd like to be someone who helps rescue the child," says Alicia, "and then helps recover the child's soul."