
Richard Allen Dysart (March 30, 1929 – April 5, 2015) was an American actor. He is best known for his role as senior partner Leland McKenzie in the television series L.A. Law (1986–1994), for which he won a 1992 Primetime Emmy Award as Outstanding Supporting Actor in a Drama Series after four consecutive nominations. In film, he held supporting roles in The Hospital (1971), Being There (1979), The Thing (1982), Mask (1985), Pale Rider (1985) and Wall Street (1987).
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The Thing
1982 · as Dr. Copper

Back to the Future Part III
1990 · as Barbwire Salesman

Wall Street
1987 · as Cromwell

Pale Rider
1985 · as Coy LaHood

Mask
1985 · as Abe

Hard Rain
1998 · as Henry Sears

Panther
1995 · as J. Edgar Hoover

Being There
1979 · as Dr. Robert Allenby

Petulia
1968 · as Motel Receptionist

The Falcon and the Snowman
1985 · as Dr. Lee

Prophecy
1979 · as Trevor Isley

The Lost Man
1969 · as Barnes

The Hospital
1971 · as Dr. Welbeck

The Hindenburg
1975 · as Lehman

Warning Sign
1985 · as Dr. Nielsen

Meteor
1979 · as Secretary of Defense

Day One
1989 · as President Harry S. Truman

The Day of the Locust
1975 · as Claude Estee