There may be a chilling reason why Hollywood hearthrob Johnny Depp still looks just as boyish as ever at age 41: "He's a vampire," charges a top expert in the occult.

"Johnny Depp has not aged visibly since he appeared in the TV series 21 Jump Street in 1987," says researcher Albert Linkway, author of the upcoming book, Nosferatu: The Untold Story of Vampires in Hollywood.

"We cannot discount the possibility that Mr. Depp was simply blessed with 'good genes'. Nor can we discount the possibility that he has joined the ranks of the undead."

Vampires have permeated Hollywood since the silent era, according to the expert.

"It's believed the curse dates back to Rudolph Valentino, who brought the infection over from Europe," he reveals.

That Johnny's chisled good looks have not faded with time isn't the only fact that raises suspicion. The expert points to other telltale signs:

* Johnny's mysterious career resurrection. After years languishing in obscure flops like Benny and Joon and The Astronaut's Wife, the star is now hotter than ever, winning raves for his performance in his latest flick, Finding Neverland. "This is typical of actors who've been vampirized," notes the expert. "A performer who's been written off as a has-been is suddenly considered 'magnetic' and is on everyone's A-list."

* He frequently wears sunglasses -- a common trait of bloodsuckers, who must use heavy sunblock and shades to ward off deadly solar rays.

* He resides in France. "As anyone who's read an Anne Rice novel knows, France is a hotbed of vampiric activity," the researcher points out.

* Has hypnotic eyes. One starlet who encountered Depp told Linkway, "If he had asked to drink my blood I would have let him on the spot."

* In Finding Neverland, he plays the author of Peter Pan. Notes Linkway: "This may be a subtle message to those in the know that he's become on of the real 'Lost Boys.'"

Just because Johnny may be fond of human blood doesn't mean you should whip out a stake instead of asking for an autograph, the expert cautions.

"Most Hollywood vampires do not attack strangers in dark alleyways," explains Linkway. "If Mr. Depp truly is one of the Undead, he probably has blood shipped to his mansion -- or it's willingly donated by his adoring female fans."

Johnny won't be able to remain in the public eye without aging forever.

"At some point, he may go into seclusion, as the reputed vampire Greta Garbo did," says Linkway. "Or he may fake his own death."

"But most likely, he will do as Cary Grant did: he'll begin to 'age gracefully' with the help of Hollywood makeup artists who add dignified gray to his hair with each passing year."