Regarding ethical non-monogamy this film is highly overrated.
Nonmono rating: 10/4
Many mention this movie as one of the most important movies about polyamory, but if somebody wants to understand ethical non-monogamy from this film may arrive at very bad consequences. I won't recommend it as a first, introductory movie. I tell more with spoilers below.
The Dreamers (2003) 115min | Drama, Romance | 20 February 2004 (USA)
Director: Bernardo BertolucciWriter: Gilbert AdairStars: Michael Pitt, Louis Garrel, Eva GreenSummary: A young American studying in Paris in 1968 strikes up a friendship with a French brother and sister. Set against the background of the '68 Paris student riots.
Countries: UK, France, Italy, USALanguages: English, French
I also have some critical notes but it may spoiler the movie. Click on the red button if you still want to read it!