"See! See the tracks!" she remembers him saying. "He knew about tracks, and could tell you about yardage and everything. It's unbelievable. ... He knew that underground system better than he knew his name."

Darius, who now lives with his parents in Winston-Salem, N.C., says that he is fascinated with every aspect of this means of transportation, "the people, the life, the way the train operates, how it all fits together."

By the time he was a teenager, Darius says he talked his way into train yards and employee-only areas of the E and F subway trains, just by saying that one of the workers was his uncle.

"People taught me down there, especially on weekends because there were no big bosses," he says.

He knew so much, he says, that one night when he was 15, a conductor asked him to take over the end of his route. "First I declined, and then said, OK, why not," Darius remembers.

Darius says that the conductor got off the train at 34th Street, while Darius continued on "down the road."

He says he picked up passengers at every stop and discharged the train at the World Trade Center. To Darius, it was business as usual.

"He loved that train so much," Elizabeth says. "He put his heart and soul into it. He wasn't going to do anything to hurt anybody."

Arrests and Asperger

That incident led to the first of Darius McCollum's nearly two dozen arrests for his actions related to the transportation system.

"Once he got a taste of that subway train and they let him drive," Elizabeth says, "he wasn't coming home."

She says she had never understood what could be triggering Darius' behavior until his diagnosis of Asperger syndrome in 2002.

In contrast to many individuals who have autism, people who have Asperger syndrome are often adept at communication and have good language skills, Klin says.

Elizabeth says that Darius fits this description. He transferred among several school systems, which Elizabeth says was related to his high intelligence; he was completing junior high-level work when he was only 8.

"He does everything so fast, in a hurry. ... After he finished, he needed more to do," she says.

However, this educational aptitude does not carry over to their communication skills, Klin says, so people who have Asperger syndrome tend to have difficulty with social relationships.

"They are very much at the mercy of others," Klin says. "They are extremely vulnerable to be the victims of pranks."

"After the diagnosis, he had been sent to us," says Michael John Carley, the executive director of GRASP, who also has Asperger syndrome. "There was the usual amount of huge relief that you see in most adult diagnoses. Suddenly there is a reason for so much that has gone on in the past that you haven't been able to explain."

Though Darius hasn't participated much in GRASP, Carley still stays in touch with him, even during Darius' times in jail.

"He is a very well-spoken, very likable guy, which is really hard to believe when you look at the iconography of someone who's spent more than half of his adult life behind bars," Carley says.

The solution to his criminal problem, Carley says, would have been for the Manhattan Transportation Authority to hire him. "He would have been their best employee."

Darius agrees, saying that he is "overqualified" for a position there but that his criminal record has prevented it.

The New York City Transit declined to comment on his actions or any personnel inquiries.

"I figure that if I had gotten in the system the way I wanted to, I should be general superintendent or chief by now," he says.

A Turning Point?

After his most recent arrest, Darius faces a decision.

"He has a very, very hard choice to make," Carley says. Darius can try to make a life for himself or he can continue with his criminal behavior, he explains.

Darius says that he has chosen his path already.

Though he loves New York, he says he's trying to get a job where people don't know as much about his reputation. He'd like to get certified as a track inspector in a Southern state and start working on small railroads.

When he was younger, Darius says he didn't think about how risky it was for him to operate trains without official instruction. But as he's gotten older, he understands the concern.

"I think about how dangerous it can be now ... how more people could be hurt, even though I don't do anything when I'm down there," he says about his time spent in the subway recently.

Still, he adds, "I don't go down there to hurt anybody. I just go down there because I still love the system."