Keira Knightley in LAST NIGHT First Picture

Take a look at the first picture of Keira Knightley in LAST NIGHT.
Last Night follows a married couple (Keira Knightley and Sam Worthington), apart for one night, during which she runs into an old flame (Guillaume Canet). As for him, well he is on a business trip with a colleague (Eva Mendes) he is attracted to.
Will they or won’t they? Well, I don’t have the answer, but I want to find out.
Last Night will be Massy Tadjedin’s directorial debut.
(Source: EW)
I am curious as to the gay aspect of the movie. I noticed on the imdb.com keyword spoilers there was the word gay. So, I am now curious. If either of these characters turn out to be gay I will definitely NOT be seeing this movie. I don’t think I’ll see it to begin with anyway because honestly haven’t we all had enough of everyone cheating on their significant other?