Several of Heath Ledger's friends, including exes Michelle Williams and Naomi Watts, open up about the actor in the upcoming issue of Interview magazine, Entertainment Tonight reported.

"I think that the interesting thing about Heath, which maybe people have only really fully discovered in his death, is how vulnerable he was," Williams says, in the issue, according to the entertainment news program. "You can pick up on it in his performances, but it's easy to overlook because he was so physical and beautiful and strong and masculine. But there was always that underlying sensitivity. That's who he was."

Watts told the magazine — to hit stands March 18 — that Ledger never liked the attention his acting career brought him, but enjoyed the fact he was being recognized for his talent.

"I think he wanted to be someone who was doing the observing — not the one being observed," Watts says, according to Entertainment Tonight. "He hated not being able to go about his life in an ordinary way. But I think that, deep down, he enjoyed that he was being recognized for his talent. I think he was starting to own that and that's the deepest tragedy, in terms of his work. He was just beginning to own it and embrace it."

Friends Philip Seymour Hoffman and Ellen DeGeneres are also interviewed for the piece.

Ledger was found dead in his Manhattan apartment from an apparent drug overdose in January.

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