[1] At age 16, in 1942, he directed and co-starred in a (9 minute) short version of Edgar Allan Poe's The Fall of the House of Usher.

Harrington had links to Thelema shared with his close associates Kenneth Anger and Marjorie Cameron who frequently acted in his films.

[5] Harrington was the driving force in rediscovering the original James Whale version of The Old Dark House (1932, Universal Pictures).

Although the rights to the original story had been sold to Columbia Pictures for a remake, he persuaded George Eastman House to preserve it.

Harrington made two television movies based on screenplays by Robert Bloch: The Cat Creature (1973) and The Dead Don't Die (1975).

Throughout the 1970s and 1980s, Harrington directed episodes of television series such as Baretta, Dynasty, Wonder Woman, The Twilight Zone and Charlie's Angels.

Financing of the film was partly accomplished through the Shrecks' brokering of the sale of Harrington's signed copy of Crowley's The Book of Thoth.