Biography
Robert Langford Modini Stack (January 13, 1919 – May 14, 2003) was a multilingual American actor and television host. In addition to acting in more than 40 films, he also appeared on the television series The Untouchables and later served as the host of Unsolved Mysteries.
Born in Los Angeles, California, Stack spent his early childhood growing up in Europe. Becoming fluent in French and Italian at an early age, and he did not learn English until returning to Los Angeles. Stack achieved minor fame in sporting, winning multiple championships including setting two world records and winning multiple honors in skeet shooting
Stack studied drama at Bridgewater State College, earning his first Hollywood role at the age of 20 and continuing to star in numerous roles throughout the early 1940s.
After serving in the military, Stack returned to Hollywood to star in numerous films including stand out roles in The High and the Mighty (opposite John Wayne) and Written on the Wind (1957), for which he was awarded an Academy Award for Best Supporting Actor.
Stack later moved on to televised dramatic series, depicting the crime-fighting Eliot Ness in The Untouchables (1959–1963), which earned him a best actor Emmy Award in 1960. Stack also starred in multiple drama series, before returning to film, this time in comedies to satirize his famed stoic and humorless demeanor.
He began hosting Unsolved Mysteries in 1987, and served as the show's host throughout it's entire original run from 1987 to 2002.
Filmography
Cast Credits

Unsolved Mysteries: Behind the Legacy
Character: Self (archive footage)
MOVIE • 2023

Yellowface: Asian Whitewashing and Racism in Hollywood
Character: (archive footage)
MOVIE • 2019

These Dead Souls
Character: (archive footage)
MOVIE • 2018
Acting for Douglas Sirk
Character: Self (archive footage)
MOVIE • 2008

Unsolved Mysteries Volume 1: UFOs
Character: Host
MOVIE • 2004

Butt-Ugly Martians
Character: Stoat Muldoon (voice)
TV • 2002

Lana Turner... a Daughter's Memoir
Character: Self
MOVIE • 2001

Killer Bud
Character: The Gooch
MOVIE • 2001

Recess: School's Out
Character: Superintendent (voice)
MOVIE • 2001

Mumford
Character: Himself
MOVIE • 1999

Sealed with a Kiss
Character: Sumner Ethridge
MOVIE • 1999

Hercules: Zero to Hero
Character: Narrator (voice) (archive sound)
MOVIE • 1999

The Y2K Crisis
Character: Host
MOVIE • 1999

Hercules
Character: Bob (voice)
TV • 1998

BASEketball
Character: Robert Stack
MOVIE • 1998

Barbara Stanwyck: Straight Down The Line
Character: Self
MOVIE • 1997

The Angry Beavers
Character: Narrator (voice)
TV • 1997

King of the Hill
Character: Reynolds Penland (voice) (uncredited)
TV • 1997

Beavis and Butt-Head Do America
Character: Agent Flemming (voice)
MOVIE • 1996

Suddenly Susan
Character: Robert Stack
TV • 1996