Jack Grinnage (born Jack Eugene Stewart, January 20, 1931) is an American actor with a film and television career spanning seven decades. Born in Los Angeles, Grinnage made his first television appearances in 1954. The following year, he played Moose – one of three teenage rebels who chase James Dean – in Rebel Without a Cause (1955). Rebel Without a Cause was his first film where he received a screen credit.
Grinnage continued to play supporting roles or bit parts in films like King Creole (1958) with Elvis Presley (in a crucial role as a mute gang member), Spartacus (1960) and The Private Navy of Sgt. O'Farrell (1968). He also played an errant but sympathetic boy in the Twilight Zone episode “The Mind and the Matter”. In 1961, he appeared in the Broadway musical The Billy Barnes People. Between 1974 and 1975, he had a supporting role as Independent News Service reporter Ron Updyke in the mystery series Kolchak: The Night Stalker. In 2009, Grinnage played the role of Marvell, the replacement janitor, in two episodes of Scrubs. His most recent credit is the television series The Kids Are Alright (2018).
2001
as Marvell
1996
as Self - 'Moose' (archive footage)
1988
as Himself
1978
as Airport Manager
1976
as Ron Updyke
1976
as Ron Updyke
1974
as Ron Updyke
1970
as Driver (uncredited)
1968
as Pvt. Roberts
1963
as Seaman (uncredited)
1960
as Petitioner (uncredited)
1959
as Henry
1959
as Dink
1958
as Leach
1958
1958
as Dummy
1958
as Delivery Boy
1955
as Moose
1955
as Andy Wirth
1955
as Gus
1955
as Raffie