'Blue Is the Warmest Color' Director, Stars on 'Difficult' Shoot: We Filmed 'All the Time' (Video)

Actresses Lea Seydoux and Adele Exarchopoulos tell THR helmer Abdellatif Kechiche shot footage constantly -- even as they napped on set.

Critically acclaimed French drama Blue is the Warmest Color hits U.S. theaters this weekend after making headlines for its controversial sex scenes and accusations of abusive on-set behavior from director Abdellatif Kechiche.

Last month, Kechiche questioned whether the film should even be released and this week publicly lashed out at star Lea Seydoux for criticizing his methods in the press.

Back in May, before the war of words erupted, Kechiche, Seydoux and star Adele Exarchopoulos sat down with The Hollywood Reporter during the Cannes Film Festival, where the love story won the Palme d'Or.

PHOTOS: 25 of Fall's Most Anticipated Movies

Kechiche said his stars were "obviously the best choice" for his film.

"They have two different but complementary personalities. I had an intuition that I had to make the movie with them," Kechiche said.

Exarchopoulos said there was no real schedule to shooting with Kechiche, because he loved to improvise and would shoot anytime, anywhere.

"Even in the train on our way back to Paris eating a cake, and he loves the way you are doing it, he will shoot it," Exarchopoulos said. "If you are sleeping during a break, he will shoot it. Anytime and all the time. Sometimes we would get to the set and he won't shoot anything. Other times, we would be tired, wondering when he would stop."

Seydoux, who is nearly a decade older than her co-star and onscreen love interest Exarchopoulos, said their personalities complemented each other despite the age difference.

STORY: 'Blue Is the Warmest Color' Director Slams 'Arrogant, Spoiled' Star in Open Letter

"I'm shy and she's not, so it was a very good combination. I needed that. Sometimes it was hard and difficult to be in this film," Seydoux said.

Exarchopoulos agreed that her co-star was essential to bringing out the best in her own performance.

"Lea was such a good friend," Exarchopoulos said. "My character would not have been the same without her. And maybe I influenced her too. It was so great to have her on that movie."