Grandpa Harry

Shadow (voice)

Jake

Harry Aldrich

Father Clemente

Brother Martin (1 episode)

G. Paul Siebriese

Self (1 episode)

Gino

Art Selwyn

Mortimer Duke / Homeless Man #2 (uncredited)

Dr. Wallace Wrightwood

Fern Stobbs

Self (1 episode)

Frank Aherne

Self (2 episodes)

Arthur Selwyn

Mortimer Duke

Stewart Coolidge (1 episode)

Henry Dobson (1 episode)

Hollis Witkin (1 episode)

Harry Whitehead (1 episode)

Armand Beller

(1 episode)

Dr. Norman Marsh (1 episode)

(1 episode)

Otis Ramsey

(1 episode)

Frank Simpson (1 episode)

Col. Flanders

Commander Taylor

Director (1 episode)

Uncle George (1 episode)

Justin Travers

Edward Shelley

Self (2 episodes)

Whitman Saunders (1 episode)

Collie McCullough (1 episode)

Self - Co-Host (3 episodes)

Self (2 episodes)

Self (1 episode)

Senator Alex S. Simon

Sam Waterman (1 episode)

Self (1 episode)

Harry Graves (1 episode)

Self (2 episodes)

Self (1 episode)

Self - Panelist (1 episode)

(1 episode)

John Gayle

Richard W. Courtland

Joe Grange

Hiram Stephen Maxim

Joseph Jefferson 'Joe' Parker

Don Ameche

Kenneth Harvey

Bingo Harper

Lew Marsh

Henry Van Cleve

Ken Douglas

Pedro Sullivan

Dwight Dawson

'Mitch' Mitchell

John Hathaway

Lloyd Lloyd

Phil O'Neil (Credits) / Phil 'Mac' McNeil

Larry Martin / Baron Manuel Duarte

Ricardo Quintana

Chris Bern

Edward Solomon

Stephen Foster

Mike Connors

Alexander Graham Bell (archive footage)

Alexander Graham Bell

Tibor Czerny

D'Artagnan

Dick Court

David Brassard Jr.

Charlie Dwyer

Jack O'Leary

Jimmy Hall

Tracy Egan

George Macrae

Peter Nostrand

Martin J. Canavan

Bob Harris

Dr. Rudi Imre

Alessandro

Karl Freyman / Mario Signarelli