Tommy Trinder
— Tommy Taylor
Frances Day
— Poppaea
Sonnie Hale
— The Professor
Francis L. Sullivan
— Nero
Diana Decker
— Lydia
Elisabeth Welch
— Nora
Mary Clare
— Volumnia
Ernest Milton
— Titus
Frederick Piper
— Auctioneer
Robert Wyndham
— Lionkeeper
Russell Thorndike
— High Priest
Danny Green
— Lictor
James Robertson Justice
— Centurion of the 8th Legion
Kay Kendall
— Girl (uncredited)
Alec Mango
— Secretary (uncredited)
Bill Shine
— Minor Role (uncredited)
Julie Suedo
— Señorita Àlvarez (uncredited)
Frank Tickle
— Master of Ceremonies (uncredited)