Roddy McDowall

Caesar

Natalie Trundy

Lisa

J. Lee Thompson

Director

Francis De Sales

Auction Attendee (uncredited)

John Randolph

Commission Chairman

Buck Kartalian

Frank - Gorilla

Severn Darden

Kolp

Lou Wagner

Busboy

James Bacon

Ape (uncredited)

William Bryant

Man at Auction (uncredited)

Don Murray

Breck

Ricardo Montalban

Armando

Hari Rhodes

MacDonald

Asa Maynor

Mrs. Riley

Joyce Haber

Zelda

H.M. Wynant

Hoskyns

David Chow

Aldo

John Dennis

Policeman

Paul Comi

2nd Policeman

Gordon Jump

Auctioneer

Dick Spangler

Announcer

Hector Soucy

Ape With Chain

Rayford Barnes

Riot Control Commander in Plaza (uncredited)

Jean Byron

Book Store Owner (uncredited)

Sam Chew Jr.

Controller (uncredited)