Under the lens of the auteur theory, it’s purely – thematically and aesthetically – an Adrian Lyne film; from the soapy production, to the story centered on sexually liberating behavior and the way this can threaten the American nuclear family.
If Fatal Attraction had ended with its alternate ending, then it – along with 9½ Weeks - would sit with Unfaithful as some kind of unofficial Lyne trilogy that dwell on very similar ideas within the blurred lines of erotic thriller conventions.
The reason Unfaithful comes out as the best of the three is the sincerity – and being Lyne’s (as of today) latest release, it exists as the first film in his oeuvre that actually embraces the Lyne style…