Man Convicted After Real Life 'Catch Me If You Can' Spree Reveals What Drove Him to Life of Lies

— -- Matthew Scheidt, a convicted felon who became infamous as a teen for impersonating a physician assistant at a Florida hospital and a police officer in Miami, now tells ABC News he had started weaving his own fantasy world of lies in grammar school.

As a child, Scheidt said he lived in a trailer in central Florida with his mother, who was arrested in 2002 for possession of crystal meth, but he starts out lying to schoolmates about where he really lived.

"Every time I would walk to the bus, you know, I would make up these little fibs to kids that I was in school with that, 'oh no, I don't live there. I live in a nice house across the street,'" Scheidt, now 21, told ABC News' "20/20"

While the other kids played sports, Scheidt said he tried to read about medicine and watched the TV dramas, "E.R." and "Grey's Anatomy." When he was just 11 years old, Scheidt said he lied about his age to volunteer at a Florida hospital, where the minimum age for volunteers was 14. He studied medical terminology, which he said he would sometimes use in conversation.

“If we were talking about something in the medical field, I would probably put out a word or two to make it sound like I knew what I was talking about, even though I had no idea,” said Scheidt.

His stint there was cut short when hospital officials caught him with a stethoscope in his pocket, allegedly masquerading as a nurse. But that was just the beginning.

Scheidt earned national attention when he was 16 years old after he was caught in August 2011 pretending to be a physician assistant at another Florida hospital, Osceola Regional Medical Center in Kissimmee. He wore scrubs, a stethoscope, and a physician assistant ID badge. He examined patients, used medical terminology and even performed CPR on a patient. When his case went to trial, it was compared to the Hollywood movie, “Catch Me If You Can.”

By 16, Scheidt said he was living on his own, out of school and taking high school courses online. His interest led to a summer job in a local doctor’s office as a medical file clerk, which had him running errands to Osceola Regional Medical Center. One day, Scheidt lied about being a physician assistant student to obtain an ID badge that gave him access to the emergency room for weeks.

“I lied and said that I was a student, I was a PA student, and that I wanted to shadow in the ER,” he said. “I had no idea that, by just going there, [saying] ‘oh, I'm a student,’ that can’t be illegal. If worse came to worse, and the cops got involved or something, I could fall back on, saying that I was just there shadowing [and tell] them I was a student.”

Scheidt said he fell in love with the environment, but he didn’t really know what he was doing, and one day, the 16-year-old was called on during an emergency.

“[A patient] ended up overdosing on medication, and one of the nurses ended up coming out of the hallway and screaming, you know, that she needs help, I guess, that the patient was coding,” Scheidt recalled. “The physician [pointed] at me and [told] me that … I need to start CPR. That’s when I started doing CPR on her.”