The lasso of truth is as much a part of Wonder Woman’s mythos as the fact that she’s an Amazon and wears a sparkly tiara. But what some don’t know is that the also has real world origins: the man who created Wonder Woman is the same guy who invented the lie detector test.

A new clip from the upcoming Professor Marston and the Wonder Women details this fact, plus Marston himself (Luke Evans) waxing poetic about how he created the Wonder Woman character to encourage girls to follow their dreams and find their own strength. Professor Marston explores the origins of Wonder Woman through the eyes of her creator and the two women he loved who inspired him to create one of the best superheroes ever written.

Here’s the film’s official synopsis:

In a superhero origin tale unlike any other, the film is the incredible true story of what inspired Harvard psychologist Dr. William Moulton Marston to create the iconic Wonder Woman character in the 1940's. While Marston's feminist superhero was criticized by censors for her 'sexual perversity', he was keeping a secret that could have destroyed him. Marston's muses for the Wonder Woman character were his wife Elizabeth Marston and their lover Olive Byrne, two empowered women who defied convention: working with Marston on human behavior research -- while building a hidden life with him that rivaled the greatest of superhero disguises.

Professor Marston and the Wonder Women opens in theaters on October 13.

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