Sex is a 1920 American silent drama film directed by Fred Niblo, written by C. Gardner Sullivan, produced by J. Parker Read, and starring Louise Glaum.

The release of Sex, with its provocative title and explicit scenes of seduction and debauchery, made it the subject of controversy among censors and commentators.

The film's plot centers on Adrienne Renault (played by Louise Glaum), the beautiful queen of the Midnight Follies at the Frivolity Theater.

[2] In another scene of debauchery, the film depicts a party at which "stage-door johnnies drink out of women's slippers and scantily clad chorines slide down banisters, their undergarments visible to all and sundry".

The film's final intertitle reads, "The standards of morality eternally demand that the naked soul of Sex be stripped of its falsehoods – which can only be atoned for through bitter tears.

A Massachusetts newspaper gave the film the following review: Sex, the wonderplay of the season ... is startling, even bold in spots, but very, very nice.

... A problem, beautifully presented and cleverly analyzed that leaves us with a sense of the infinite at the end -- which is distinctly unusual -- and which is entirely free from the sticky-sweet sentimentality of too many photoplays is the theme of sex.

[5]A Pennsylvania newspaper wrote: "We have heard a great deal in the past year about 'pictures with a soul' but we never quite got the significance of the 'soul-picture' until we saw 'Sex' with Louise Glaum as the star.

"[6] A Chicago newspaper called it "a lesson to thousands of frivolous creatures who fool themselves into believing that youth lasts forever, that pleasure is life's chief object and that one can violate the laws that regulate our domestic lives and get away with it".

[10]The film was a box office success, and the Los Angeles Times reported that it had led to a war being declared in some quarters against "sex pictures".