From the L.A. Times news obit:

John Gregory Dunne, the journalist, screenwriter and novelist who chronicled the Hollywood movie industry in his book "The Studio," then went on to write for film, died unexpectedly Tuesday evening as he sat down to dinner with his wife, author Joan Didion. He was 71.

Dunne died of a heart attack in the couple's New York City home, where the longtime residents of California had been living, his wife said.

Dunne's first books were works of hard-hitting journalism: The first, "Delano: The Story of the California Grape Strike," appeared in 1967 and followed Chicano labor leader Cesar Chavez. His second, "The Studio," was published in 1969 and detailed the inner workings of Twentieth Century Fox. In 1974, "Vegas: A Memoir of a Dark Season" explored the author's depression after a nervous breakdown.