Paul Benedict, the actor who played the eccentric English neighbor Harry Bentley on the sitcom "The Jeffersons," was found dead Monday at his home on Martha's Vineyard, Mass. He was 70.

Authorities were investigating the cause of death, said his brother, Charles.

Benedict's oversized jaw and angular features were partly attributed to acromegaly, a pituitary disorder that was first diagnosed by an endocrinologist who saw Benedict in a theatrical production.

He underwent medical treatment to prevent the disease from spreading while he continued to act -- and used his facial features for comic effect.

As an actor, Benedict built a career portraying loony characters in films such as "The Goodbye Girl" (1977), "The Man with Two Brains" (1983) and "The Addams Family" (1991). He also appeared in the Christopher Guest comedies "This Is Spinal Tap" (1984), "Waiting for Guffman" (1997) and "A Mighty Wind" (2003). On the PBS children's show "Sesame Street," Benedict was the Mad Painter who painted numbers everywhere.

But he was mainly known for his role as Bentley on "The Jeffersons," which ran on CBS from 1975 to 1985. He left in 1981 to pursue other projects but returned in 1983. Benedict later said he hadn't expected the show to last more than a season and only agreed to the part because producer Norman Lear kept asking him to reconsider.

The accented speech that he used even offstage led many to assume that Benedict was British, but in fact he was born Sept. 17, 1938, in Silver City, N.M. He was the youngest of six children; his father a doctor, his mother a journalist.

"When I was 5 years old, from the first time I went to the movies, I knew I wanted to be an actor," Benedict told The Times in 1992.

After growing up in Boston, Benedict attended the city's Suffolk University and began his acting career in the 1960s in the Theatre Company of Boston, performing alongside such future stars as Robert De Niro, Dustin Hoffman and Al Pacino.

On Broadway, he appeared opposite Pacino in Eugene O'Neill's two-character play "Hughie" in 1996 and played the mayor in a 2000 revival of "The Music Man."

As a stage director, he was known for taking a work in progress or a new play and laboring with a playwright to infuse it with "intelligence, sympathy and warmth -- and of course, humor," The Times reported in 1992.

His breakthrough show as a director was "Frankie and Johnny in the Clair de Lune" in 1987, closely followed by "The Kathy & Mo Show: Parallel Lives" in 1989, both two-person sleepers that became off-Broadway hits.

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