ट्रिविया

Best known as the designer of all the costumes worn in Star Trek (1966), including the uniforms.

Developed a theory that the attractiveness of clothing on women is not really dependent on the amount of skin shown - rather, it depends on the degree to which the outfit appears to be on the verge of falling off. TV Tropes calls it the Theiss Titillation Theory.

Graduated with a degree in art from the Art Center College of Design at Stanford University.

First worked in Hollywood as an assistant to Cary Grant, then known as "the best-dressed man in Hollywood.".

He used his middle name to differentiate himself from a New York clothes designer named William Theiss.

Had a reputation for being eccentric to the point of rudeness. He was extremely private, of solitary disposition, and also a perfectionist, relentlessly driving those working under him. His motto was, first and foremost: "Stop when all work is done - and not before.".