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Film 1056: Blue Is the Warmest Colour

Trivia: There was no makeup artist and hairstylist on the set. The actresses were not allowed to wear makeup for most part of the movie.

The actresses only read the script once. Abdellatif Kechiche insisted that they forget what the script said line for line, and instead asked them to improvise their scenes and really let their actions and words come out naturally and as unforced as possible.

A good portion of the B-roll footage with Adèle Exarchopoulos that ended up being used are in fact of the actress when she was out of character. The camera would be on her when she ate and even when she slept on the train while they were on their way to set. Since during this footage people kept calling Exarchopoulos the name Adèle instead of Clementine, they agreed to have the main character's name changed to Adèle.

One of the sex scenes took 10 days to film.

Adèle Exarchopoulos and Léa Seydoux wore prosthetic vaginas in the scenes in which they perform oral sex.

Léa Seydoux had her hair cropped by a barber in Paris' 18th arrondissement and dyed blue, months before the shooting began. During filming, she had to re-dye her hair every day for continuity and half the time it was director Abdellatif Kechiche who did her color himself.

In preparation for her role as Emma, Léa Seydoux attended painting and sculpture lessons. She also undertook extensive reading on arts and philosophy, and visited museums before filming began. To assist her in portraying the masculine characteristics of the arts student role, the director requested Seydoux to go for training sessions to tone up her physique and also study the films of Marlon Brando and James Dean to learn their traits.

Initially planned to be shot in two months, the film took nearly five-and-a-half months.