The Unknown Purple

The Unknown Purple is a lost American silent mystery film from 1923, written and directed by Roland West. The plot centers on an inventor who, upon leaving prison, creates a strange purple light that makes him invisible. He uses this power to take revenge against his unfaithful wife and his dishonest business partner. The film premiered at the Strand Theatre in Providence, Rhode Island, on October 29, 1923.

Film historian Scott MacQueen noted that the project was inspired by "The Vanishing Men," a treatment West had hoped to film in 1921. This, in turn, drew from H.G. Wells’ novel *The Invisible Man*, which would not receive a proper film adaptation until 1933. The movie was adapted from a stage play co-written by West and Carlyle Moore. Comedian Johnny Arthur made his feature-length debut in this film.

At its premiere, the manager of the Strand Theatre reported to *Moving Picture World* that the film "opened with capacity business." Contemporary reviews were positive: *Variety* called it "exceptionally well-made picture—among the best of its type—a mystery," praising Oliver Marsh’s photography and the performances of Henry Walthall and Alice Lake. Mary Kelly of *Moving Picture World* described the production as "elaborate and impressive," noting that the only weak point was the lack of comedy.