John Mills (Masterman Finsbury), Ralph Richardson (Joseph Finsbury), Michael Caine (Michael Hubert Gregory Finsbury), Peter Cook (Morris Finsbury), Dudley Moore (John Finsbury), Nanette Newman (Julia Finsbury), Tony Hancock (Detective) more..., Peter Sellers (Doctor Pratt), Cicely Courtneidge (Major Martha), Wilfrid Lawson (Peacock), Thorley Walters (Patience), Gerald Sim (1st Undertaker), Peter Graves (Military Officer), Irene Handl (Mrs. Hackett), Norman Bird (Clergyman), John Le Mesurier (Doctor Slattery), Hilton Edwards (Lawyer), Norman Rossington (1st Rough), Diane Clare (Mercy), Tutte Lemkow (Strangler), Jeremy Lloyd (Brian Allen Harvey), James Villiers (Sydney Whitcombe Sykes), Graham Stark (Ian Scott Fife), Dick Gregory (Leicester Young Fielding), Nicholas Parsons (Alan Frazer Scrope), Willoughby Goddard (James Whyte Wragg), Valentine Dyall (Oliver Pike Harmsworth), Leonard Rossiter (Vyvyan Alistair Montague), Hamilton Dyce (Derek Lloyd Peter Digby), Timothy Bateson (Clerk), Donald Oliver (Gunner Sergeant), Totti Truman Taylor (Lady at Launching), Jeremy Roughton (Bugler), Frank Singuineau (Native Bearer), Michael Lees (Young Digby), Avis Bunnage (Queen Victoria), Gwendolyn Watts (Maidservant), Vanda Godsell (Mrs. Goodge), Marianne Stone (Spinster), John Junkin (1st Engine Driver) and others.

Lloyd Osbourne (Novel), Julie Harris (Costume Design), Larry Gelbart (Writer), Robert Louis Stevenson (Novel), Burt Shevelove (Writer), Gerry Turpin (Cinematography), Larry Gelbart (Co-Producer) more..., Jack Rix (Associate Producer), Alan Osbiston (Editor), Burt Shevelove (Co-Producer), Bryan Forbes (Producer), Ray Thorne (Assistant Editor), Ray Simm (Set Designer), Roy Ponting (Wardrobe Master), Laurel Staffell (Wardrobe Master), Christopher Dryhurst (Assistant Director), Michael Sarafian (Assistant Camera), Basil Newall (Makeup Artist), George Hill (Construction Manager), Paul Rabiger (Makeup Artist), Bill Daniels (Sound Recordist), Ronnie Taylor (Camera Operator), Donald Toms (Production Manager), Ken Barker (Sound Recordist), Maude Onslow (Hairdresser), Penny Daniels (Continuity), Teddy Mason (Sound Editor), Gus Lloyd (Sound Assistant), Ted Lockhart (Grip), George Courtney Ward (Still Photographer), George Ball (Props), Alfred Waye (Props), John L. Hargreaves (Producer's Assistant), Peter James (Set Dresser), Robert Ellis (Title Designer), Gerry Turpin (Director of Photography), John Barry (Music Arranger), John Barry (Conductor), John Barry (Original Music Composer),