Elisha Cook Jr.
Elisha Vanslyck Cook, Jr. (December 26, 1903 – May 18, 1995) was an American character actor who made a career out of playing cowardly villains and weedy neurotics in dozens of films. He was perhaps most noted for his portrayal of the "gunsel" Wilmer, who tries to intimidate Humphrey Bogart's Sam Spade in The Maltese Falcon. Description above from the Wikipedia article Elisha Cook, Jr, licensed under CC-BY-SA, full list of contributors on Wikipedia
Filmography
Bonanza
Perry Mason
Star Trek
Mannix
The A-Team
Magnum, P.I.
Ironside
The Fugitive
Batman
Night Court
Quincy, M.E.
Climax!
Simon & Simon
The Twilight Zone
Rawhide
The Life and Legend of Wyatt Earp
ALF
Starsky & Hutch
The Wild Wild West
Burke's Law
Thriller
The Odd Couple
McCloud
Alfred Hitchcock Presents
Cimarron Strip
Switch
Gunsmoke
Peter Gunn
Baretta
Bat Masterson