Definitely not the first female/female kiss in a mainstream film. First threesome shown? I'm not sure, but I'm leaning towards no...
"Now what kind of man are YOU dude?"
Seriously???? The movie came out in 1971. do you really think cinema made it through the sixties without a single lesbian kiss or FFM three-way?
shareIn terms of mainstream cinema, D.H. Lawrence's "The Fox", made in 1967 and released (it was a big hit) by a subsidiary of Warner Bros. is probably the breakthrough film in this regard. Besides its love affair between Anne Heywood and Sandy Dennis, it concerned a tortured triangle involving the male intruder Keir Dullea, who made the film after he shot "2001: A Space Odyssey" but saw it released before the lengthy post-production (SPFX) Kubrick film was completed and eventually released, making him pretty prominent with two big movies in a row.
Dullea's character, symbolized by the fox, was the intruder into the women's world, just as Eastwood intruded into the all-female world in "The Beguiled". Perhaps Sofia Coppola could turn to D.H. Lawrence for an abundance of inspiration in his novels, both filmed and unfilmed to date.