
Wally Cox was a beloved character actor who made his mark in television and ranks as one of the medium's most memorable performers. His ability to show his range likely was limited by his short stature, slight frame, and high-pitched voice, which along with his talent for being very funny, made him ideal for comedy parts such as his memorable turn as Professor P. Caspar Biddle in "The Bird-Watchers" episode of The Beverly Hillbillies (1962) in 1966. His television persona was that of a shy, timid man in horn-rimed glasses who spoke in a tentative, though distinctly enunciated, voice. It was a persona that his long-time friend Marlon Brando said was completely at odds with the real man.
Cox always will be remembered as the eponymous "Mr. Peepers" and the voice of "Underdog," but he was an actor of wider talents seldom used by the industry, as can be seen in his turns as the sonar operator in The Bedford Incident (1965) and as the potential suicide Wally Haverstraw in The Bill Cosby Show (1969) episode "Goodbye, Cruel World" in 1970. Dying unexpectedly on February 15, 1973, from what some newspapers described as an accidental overdose of sedatives but which Marlon Brando in his autobiography said was a heart attack, Wally Cox's cremated remains were kept hidden in a closet by his old friend for three decades. According to Brando's son Miko, both his father's and Cox's ashes were scattered at the same time in Death Valley, California, in a ceremony following Brando's death, thus reuniting the lifetime friends.

A Guide for the Married Man
1967 · as Technical Adviser

Ironside
1967 · as Scoutmaster

The Night Strangler
1973 · as Mr. Berry

Bob Hope's World of Comedy
1976 · as Self - Tribute Montage (archive footage)

Spencer's Mountain
1963 · as Preacher Goodman

The Bedford Incident
1965 · as Seaman Merlin Queffle

The Yellow Rolls-Royce
1964 · as Ferguson

State Fair
1962 · as Hipplewaite

Morituri
1965 · as Dr. Ambach

The Barefoot Executive
1971 · as Mertons

Reel Horror
1985 · as Clyde (archive footage)

Magic Carpet
1972 · as Harold Kane

The Boatniks
1970 · as Jason

Fate Is the Hunter
1964 · as Ralph Bundy

The One and Only, Genuine, Original Family Band
1968 · as Mr. Wampler

Television: The First Fifty Years
1999 · as Robinson J. Peepers (archive footage)

Hollywood Heaven: Tragic Lives, Tragic Deaths
1990 · as (archive footage)

The Young Country
1970 · as Aaron Grimes / Ira Greebe