NEW YORK (Reuters) - Michael Caine has been acting for more than 50 years and has no plans to retire. Instead the British army veteran says his career will simply "fade away" like an old soldier .

Caine, 76, says he now only takes roles he just can't refuse and that apart from two completed movies and being contracted to reprise his role as the butler in the third Batman movie, he does not yet have another film lined up.

"It's the old Mafia thing, you make me an offer I can't refuse. And it's nothing to do with the money anymore, it's to do with the script," Caine told Reuters in an interview for his latest film "Is Anybody There?". It opens on Friday in U.S. theaters.

"If a script doesn't turn up that I can't refuse, then I'm retired," he said. "There's no fanfare or announcement in the newspapers, I've just gone. I used to be a soldier and as they say ' old soldiers don't die they just fade away.'"

Caine, who served with the British army in the Korean War , said he has given one of his best performances playing a musician dying of Alzheimer's disease in "Is Anybody There?"

Clarence (Caine) strikes up an unlikely friendship with a young boy when he moves into a retirement home run by the boy's parents in rural England.

"It's one of the best movies I've ever done, it's one of the best performances I've ever given," said Caine, who won best supporting actor Academy Awards for " The Cider House Rules " in 2000 and for " Hannah and Her Sisters " in 1987.

"My criteria for my performances is, and I've very seldom done it, did I disappear? Did the acting disappear? And did Clarence appear? And the answer to all those three questions is yes," said Caine.

ACTING HIS "DRUG"
Caine will also appear in "Harry Brown" -- as an elderly former Marine who lives in a housing project and becomes a vigilante when his best friend is murdered -- which he said is due to be released later this year.

He said he had no idea if and when the third Batman movie would be made, but presumed it would not be for a while as director Christopher Nolan had just started work on another movie due for release in 2010.

Early reviews of "Is Anybody There?" are applauding Caine's performance.

Reel Film Reviews says Caine "offers up an affecting, flat-out mesmerizing performance that's as strong as anything he's done in the past." Film Journal International says "Caine does a superb job conveying Clarence's subtle, then sudden, slide into senility."

Director John Crowley said that the moment Caine was suggested, it was hard to imagine anyone else in the role.

"It's incredible the amount of experience he carries with him," Crowley said of Caine, after recounting a tip that Caine learned from Marlene Dietrich and passed on to his teenage co-star Bill Milner.

For any filmmaker looking to make Caine, who describes acting as his "drug," that offer he can't refuse, he has one request after playing two elderly men.

"I keep getting made down instead of made up. Instead of trying to make me look the best I can, they make me look the worst I can," he said. "I'm now looking for a movie where I get made up."