It is unclear if the writer was aware but the central character is a psychopath and the incidents in the film are to be seen in the textbooks illustrating psychopathic behaviour*. Had this been a better production especially had it had a better lead the extraordinary nature of the (in this case) man would have been more apparent. The psychopath is likely to be be the most charming, most charismatic apparently most sincere and trustworthy person one has ever met. Hence as correctly shown in the film, the woman in complete denial of reality. They are also completely devoid of conscience or empathy - utterly indifferent to the consequences of their actions no matter how serious. Lacking a core reality they spend their lives acting hence it is first nature to them - and they are able to seamlessly act whatever part will get them what they want. One of the cheated women speaks of him "stalking her like an animal" - that is one of the characteristics along with an intense stare at those they would con and manipulate - they are watching and reading. Notwithstanding their superficial appearance their inner self is reptilian in its utter cold indifference to others.
If only an actor of the calibre of for example Martin Sheen had played the lead with his capacity for charm, charisma and intensity this would have been a disturbing and memorable film. Jailing a psychopath would not change his behaviour - it would continue in prison and fully resume after release - as the text books attest.
This is a serious topic which merits better handling and wider recognition.
*authors Hervey Cleckley and Robert D. Hare