The Invisible Man (1933)

Carroll Borland

Mark of the Vampire, 1935

Matt Willis

 as 

Andreas the Werewolf 

 in

 RETURN OF THE VAMPIRE (1943)

Fredric March, 

Dr. Jekyll and Mr. Hyde (1931)

Boris Karloff

The Old Dark House (1932)

Paul Naschy

La Maldición de la Bestia

Night of the Howling Beast

 (1975) 

Regan and Linda Blair double exposure.

 Rondo Hatton 

 (1894-1946)

Hyde by Dick Smith 

for Milton Berle Telecast

The Alien creature head helmet

Designed by H.R. Giger and mechanics by Carlo Rambaldi

1979

Boris Karloff

Abbott and Costello Meet-Dr. Jekyll and Mr. Hyde (1953)

Christopher Lee as the monster 

in 

The Curse of Frankenstein (1957)