I just saw this film again last night. You know how "It's A Wondeful Life" comes up on TV every Xmas, and some people watch it every year? I think that "Pleasantville" would be my choice for watching once a year. Not just (or even mainly) because of its polyness.I'm really surprised that nobody yet has mentioned Pleasantville, a 1998 American fantasy comedy-drama written, produced, and directed by Gary Ross. The film stars Tobey Maguire, Reese Witherspoon, William H. Macy, Joan Allen, Marley Shelton and Jeff Daniels. Here is a trailer on YouTube.
I fell in love with the Joan Allen character (the hinge in the V). Watch out for her (incendiary) discovery of orgasm (self produced)! The polyamory doesn't run right through the film (and I don't want to spoil it for you by expounding on this), but the scene at the end on the bench is just wonderful. As is the one of the son cross-examining his father in the courthouse. (I like the whole film, and it's got the best cover version of "Across The Universe" [by Fiona Apple] that I've ever heard.) I've seen it on video, dubbed into Spanish, as well as in original American (cut up into 10 minute "chapters" - and missing one chapter) on YouTube.
I watched it last night with friends (a couple), the woman being very vociferous about things that bother her on-screen. When the [film] husband says "Where's my dinner?!", my friend shouted "Get it yourself, you lazy bastard!"
... After she calmed down and started paying attention, she LOVED the film.