Twenty-five years ago, Mark David Chapman stamped his name into history by shooting four bullets into John Lennon's back — a desperate, senseless grab for the kind of fame the voice of a generation was so steeped in. Instead, all he gained was infamy.

"I want to be important," Chapman later said of his mind-set before the murder. "I want to be somebody. I was never anybody."

The journey from nobody to notorious started in Decatur, Georgia, where he grew up with his parents and sister. After high school, Chapman worked as a camp counselor at an Atlanta YMCA and was briefly enrolled at Covenant College, a Christian university in Georgia. But he dropped out, broke off an engagement and entered a dark period of depression.

In the spring of 1977, Chapman moved to Honolulu, where he attempted to kill himself using the exhaust from a car. In the following years, Chapman, a devout Christian, would take exception to Lennon's perceived anti-religion beliefs. At the height of Beatlemania, Lennon had famously proclaimed the Beatles "more popular than Jesus," and later sang in "Imagine": "Imagine there's no heaven."

At the same time, Chapman developed an obsession with J.D. Salinger's "The Catcher in the Rye," the landmark novel that focuses on a disaffected youth, Holden Caulfield, during a trip to New York City.

Though previously a great fan of the Beatles, Chapman began attaching Caulfield's favorite slander — "phony" — to Lennon. He made that assessment after seeing photos of Lennon atop his exclusive Manhattan apartment building, the Dakota.

"At some point, after looking at those pictures, I became enraged at him and something in me just broke," Chapman would explain later. "I remember saying in my mind, `What if I killed him?'"

"I felt that perhaps my identity would be found in the killing of John Lennon."

Believing himself the embodiment of Holden Caulfield, Chapman, then 25, arrived in New York City Dec. 6, 1980. Two days later, he bought another copy of Salinger's book and wrote in it, "This is my statement." He went to the Dakota and waited for Lennon.

When he arrived, Lennon politely signed an autograph for the pudgy, dark-haired, ordinary-looking fan. Chapman stayed, waiting for Lennon and his wife, Yoko Ono, to return later that evening.

"It was like a runaway train," Chapman would later say of his desire to kill Lennon. "There was no stopping it."

Just after 10:50 p.m., the couple exited their limousine and began walking into the Dakota. Chapman unloaded, hitting the 40-year-old Lennon with all but one shot. Then, without a word, he sat down and opened "The Catcher in the Rye."

The man whose songs and lyrics had meant so much to so many, died on the way to the hospital.

The outpouring of grief was immediate — as was confusion. Who was Chapman? Why did he do it?

Chapman signed a statement to police that evening: "I have a small part of me that cannot understand the world and what goes on it. I did not want to kill anybody and I really don't know why I did it."

A brief 1981 trial offered few answers. Chapman was expected to mount an insanity defense; a psychologist diagnosed him as a paranoid schizophrenic. Instead, he pleaded guilty and was sentenced to 20 years to life. He has since resided in New York's Attica Correctional facility, where he has been kept separate from the jail's general public for his own safety.

There are, of course, Beatles fans everywhere.

Chapman has not been silent since being jailed. He has given several interviews, most extensively to Jack Jones, who turned their conversations into a book entitled "Let Me Take You Down: Inside the Mind of Mark David Chapman."

It was announced just weeks ago that a movie is in the works about Chapman and the days leading up to the murder. The film will star Jared Leto as Chapman and Lindsay Lohan as a Lennon fan who befriends Chapman.

Though Ono has not publicly commented on the film, her spokesman, Elliot Mintz, has criticized a recent, two-hour "Dateline NBC" special on Chapman.

"The timing of this is macabre," Mintz said. "(Ono) thinks it's outrageous. ... It sends out a message to other disturbed people that killing is a way to fame."

Newsman Larry Kane, who recently wrote the book "Lennon Revealed," agrees.

"(Chapman) is not the story," Kane says. "He's the ending of the story, but he's not the story. The story is the 25 years of achievement that John Lennon managed, the music and poetry he left behind and the feeling of creation."

Chapman has come up for parole three times, and each time been denied. He'll again be eligible next October, but according to Charles P. Ewing, a professor of law at the University of Buffalo (SUNY), his chances are between "slim and none" of ever being paroled.

"Very few people with a life cap ever get paroled and his case has generated so much negative publicity," Ewing says.

In October, 2004, the parole board said Chapman killed Lennon for the attention, and that, "although proven true, such rationale is bizarre and morally corrupt."

Petitions have been submitted opposing his release, and Ono has, at each parole hearing, sent a letter saying that if he were set free, "myself and John's two sons would not feel safe for the rest of our lives."

The murder, she said, "managed to change my whole life, devastate his sons and bring deep sorrow and fear to the world." Releasing Chapman, would "bring back the nightmare, the chaos and the confusion once again."

Speaking to the parole board in 2004, Chapman, who has apologized a number of times for the murder, acknowledged the depravity of his notoriety:

"I deserve nothing," he said. "In some ways I'm a bigger nobody than I was before because, you know, people hate me now instead of, you know, for something positive. So that's a worse state."