A 28-year-old named Derek Luke is the talk of Hollywood thanks to “Antwone Fisher,” an incredible true-life story directed by Denzel Washington.Luke’s own story is almost as unbelievable.

A few years ago, he was one of the thousands of aspiring actors in Southern California, where he had moved from New Jersey looking for his big break.

He was trying to decide whether to support himself by working for UPS – or at the gift shop on the Sony Pictures lot in Culver City.

“I was going to take the job with UPS, figuring I could use my days to audition,” he recalled with a chuckle during a recent publicity stop in Manhattan.

“A friend told me I was stupid, that my best chance of becoming an actor would be to work at Sony.”

It turned out to be one amazing piece of career advice.

Through his job at Sony selling candy, videos and trade newspapers, Luke met producers who gave him small guest shots in TV shows like “King of Queens.”

Then a fellow employee introduced him to a former studio security guard named Antwone Fisher.

Fisher was developing a script based on his triumph over adversity in the Navy, after a horrific childhood in Cleveland.

“I just knew it was a supposed-to-be place for me,” recalled Luke, who struggled himself as the son of a preacher and a postal worker in Jersey’s rust belt – Jersey City, East Orange, Woodbridge and Linden.

“It wasn’t just that the inner city was tough,” Luke said. “I wasn’t used to seeing people go after their dreams. I had to go to California to see whether I could sink or swim.”

It wasn’t easy landing the part in “Antwone Fisher,” which opens Thursday.

Washington had chosen the script for his directing debut. Luke crashed an audition uninvited and, by his own description, “bombed.”

But the project was postponed several years because of Washington’s busy acting schedule – and Luke had actually done well enough that he was asked to read for the part again.

There were four more auditions altogether, the last with Washington himself.

Several days after the last reading, Luke was walking outside the Sony store with Fisher, who had come to visit, when who should show up but Washington.

“I walked past the real Antwone and I said to Derek, ‘Hey Antwone, how’s it going?’ ” Washington recalled.

“Denzel called me Antwone,” Luke marveled, still stunned.

“It just belonged to him,” Washington said. “He was just the right person, the right spirit for the part.”

Luke said the 40-day shoot – quick by Hollywood standards – “seemed like 40 years” and that during scenes shot at sea “I got morning sickness, like I was pregnant.”

He admits he “almost shut down” from the pressure of being in every scene – playing Fisher from an abused, homeless teenager to a 25-year-old who learns to channel his rage and pursue a relationship with a Navy woman played by model-turned-actress Joy Bryant.

Luke said that what he found the most intimidating – and inspiring – were the many scenes he plays opposite Washington, who cast himself as the compassionate Navy psychiatrist who encourages Fisher to track down his mother.

“My very worst day were the first scenes we shot in his office,” Luke said. “I couldn’t get my lines to stick, it wasn’t making any sense. But Denzel was incredibly patient and helped me be honest with the material.”

The movie and Luke have been drawing praise since the Toronto Film Festival in September. Last week, he was nominated for best breakthrough performance by the Independent Spirit Awards, and more kudos seem in the offing.

His next movie, “Biker Boyz” with Laurence Fishburne, opens next month, and he’s already wrapped another adventure, “Pieces of April,” starring Katie Holmes.

And Luke’s smiling face is already ubiquitous from a series of recently launched Gap ads.

“It’s payback for folding all those slacks,” joked Luke – whose pre-Sony job was as a stock clerk at a J.Crew store in Pasadena, Calif.