A failing, has-been actress and her wealthy and asexual or impotent husband take advantage of his bad health to book a face-saving trip to Europe. The husband dies en route. During her mourning period, Mrs. Stone is forced to occupy herself in Rome with post-war society, largely comprised of bitter and now-impoverished Italian royalty and a few lightweight and false-faced inter-continental "friends." I do not understand how Mrs. Stone's character unfolds and becomes so dependent upon the gigolo who has been assigned to compensate for her years without a sex life (and bilk her of whatever money he can) by a hungry Contessa. I also don't understand how she, starved in her marriage or not, is supposed to be so constantly sexually ready at the age of "50." Nevertheless, Mrs. Stone in some respects appears to be resigned to the loss of her youth and realistic about the affair; then, in the next moment, behaves like a lovesick girl. She has a great deal going for her and with her intellectual and financial resources one wonders why she did not move on voluntarily,geographically or romantically. She did not need to be lonely or immobilized. I suppose these developments say more about author Tennessee Williams, his mindset and prejudices, and his era than reality today.
One curious character throughout the movie is a young, homeless and starving stalker, who is every bit if not more beautiful than Paolo the gigolo. He does seem to worship Mrs. Stone, who is indeed a handsome and well-put-together lady for her age. She is aware of and appears to be repulsed by his constant nearness, as he is socially beyond redemption, not just in his impoverished disarray, but his vulgar and undisciplined habits.
The gigolo increasingly abuses and humiliates her, and inevitably breaks with her under pressure from the Contessa and perhaps his own restlessness. He has cruelly teased Mrs. Stone by comparing her to others of her ilk who are typically found with their throats slit.
The final scene has Mrs. Stone flinging the keys to the gates of her villa down to the homeless stalker. You see him approach her and her standing in wait with a pained face and eyes downcast.
I did not interpret this to be a romantic or sexual scene in the least. It was chilling and tragic. The phrase I used to my husband was "suicide by psycho."