Two strangers, both married to others, meet in a railroad station and find themselves in a brief but intense affair.

On one of their usual weekly commutes into the city, two perfect strangers--Dr Alec Harvey, an esteemed suburban doctor, and Anna Jesson, a middle-class housewife--will inadvertently find love, when a bit of dirt enters Anna's eye and the good doctor comes to her rescue. Despite both being married to others, this fleeting but powerful interaction will prepare the ground for an unforeseen erotic but unconsummated love affair, as one clandestine rendezvous leads to another. Where is this intense emotional infidelity heading?—Nick Riganas

Anna (Loren) and Dr Alec Harvey (Burton) meet by chance and their casual friendship turns into a tormenting relationship. Realising the danger to her marriage, Anna avoids Alec who is unhappy in his own marriage and pursues Anna with increasing intensity. Unable to resist his charm, Anna accepts Alec's invitation to a rendezvous in a friend's apartment.