Mr. Stack died at home in Los Angeles at the age of 84, according to the Associated Press. His Broadway debut will be posthumous this summer: His recorded voice helps tell the B-movie-style musical fable, Little Shop of Horrors, about a man-eating plant and the nitwits who nurture it. Opening at the Virginia Theatre is set for Aug. 14. The Alan Menken-Howard Ashman show is currently playing a developmental run in Florida.
The cause of death was heart failure.
On TV, Mr. Stack found success playing the dead-serious Prohibition-era agent Ness in "The Untouchables." He won an Emmy for his work.
According to AP, Mr. Stack was "born into a performing arts family in Los Angeles. His great-great-grandfather opened one of the city's first theatres, and his grandparents, uncle and mother were opera singers."
A screen test when he was 20 started a long Hollywood career. He was Oscar-nominated in 1957 for appearing in "Written on the Wind." His stiff image was exploited in the film comedies "Airplane!" and "1941."