Stirling Dale Silliphant (16 January 1918 – 26 April 1996) was an American screenwriter and producer. He was born in Detroit, Michigan, moved to Glendale, California as a child, graduated from Hoover High School, and was educated at the University of Southern California. He is probably best known for his screenplay for In the Heat of the Night and co-creating the television series Route 66. Other features as screenwriter include the Irwin Allen productions The Towering Inferno and The Poseidon Adventure, adapting both films from previously published novels. In the case of The Towering Inferno, Silliphant was tasked with blending two entirely unrelated novels into a single screenplay.
Silliphant is also remembered for his now-infamous bet with Hal Warren on whether Warren could make a successful horror film on a limited budget, which was the inspiration for Manos: The Hands of Fate, and he is portrayed in the 2011 documentary / comedy feature film ""SUENO" The Dream of Hal Warren" from director Tony Trombo.
He was a close friend of Bruce Lee — under whom he studied martial arts — who was featured in the Silliphant-penned detective movie Marlowe and four episodes of the series Longstreet. Silliphant was involved in the early part of Bruce Lee's movie and TV career in America, and suggested him for action choreography work on productions like A Walk in the Spring Rain, a Silliphant-scripted film.
They had also been writing on a philosophical martial arts script called The Silent Flute (later known as Circle of Iron), with James Coburn. It was to star Lee and Coburn, and the pre-production even went to the extent of all three going to India on a location hunt.