He is known for his work in various films during the 1940s and 1950s, and as the voice of Horace in One Hundred and One Dalmatians (1961).

[2] From 1938 to 1966, Worlock appeared as a supporting actor in films including Man Hunt, Dr. Jekyll and Mr. Hyde, How Green Was My Valley, The Imperfect Lady, Singapore, The Lone Wolf in London, Love from a Stranger, Ruthless, Joan of Arc, Spartacus, One Hundred and One Dalmatians (voice-over), and Spinout.

He appeared in a number of the Sherlock Holmes films starring Basil Rathbone in the 1940s, also portraying Inspector Lestrade opposite Rathbone in The New Adventures of Sherlock Holmes.

Worlock often portrayed "professorial roles, some benign, some villainous".

[3][4] In 1924, he married actress Elsie Ferguson, with whom he had appeared in The Moon-Flower on Broadway.