Rainer Werner Fassbinder’s 1974 movie Fear Eats the Soul is as quietly amazing as ever, nationally re-released as part of a retrospective at London’s BFI Southbank. It’s the gripping tale of courageous romance between Emmi, a white Polish-German woman, and Ali, a young Moroccan man: a simple, clear story and yet with its own sophisticated moral intelligence. The film takes place among the resentfully racist anständig middle classes of postwar Munich, all of them with fear-eaten souls. This is partly a homage to the 50s domestic dramas of Douglas Sirk, but given that Sirk was still alive and working when this was made, the perspective now is different. Quite unlike Todd Haynes’s Far from Heaven (2002), a masterpiece for different reasons, it is not a pastiche, and not something in which modernity is in ironic contradistinction to a past genre. Fear Eats the Soul is urgent and contemporary: it means something relevant in 1974, and in 2017. (If it comes to homage and pastiche, I’m only just coming to terms with the way Aki Kaurismäki’s bar-room scenes are a tribute to this film.)

Causing consternation … Emmi and Ali in Fear Eats the Soul. Photograph: Ronald Grant

Brigitte Mira plays Emmi, a widowed cleaning lady who one sad rainy night stops at a bar frequented by immigrants and Gästarbeiter, presided over by the blowsy Barbara (Barbara Valentin). A lonely young Moroccan man, nicknamed Ali (played by Fassbinder’s partner El Hedi Ben Salem) gallantly asks her to dance. They go home together, fall in love and – to pre-empt her landlord’s assumption that she is illegally subletting her apartment to this man (for surely no other explanation is possible) she defiantly announces that they are getting married. And so they do, facing down their own inner fear and that of others. It causes consternation among her grownup children and her obnoxiously racist son-in-law (showstoppingly played by Fassbinder himself).

One of her sons furiously trashes her television in a rage – a direct reference to Sirk’s All That Heaven Allows. With remarkable, unself-conscious candour, Emmi reveals that she was a Nazi party member during the war, asks Ali if he has heard of Hitler and even takes him to the restaurant renowned as Hitler’s favourite, the Osteria Italiana in Schellingstrasse. She never makes any gesture of apology for her past, never hints that her feelings for Ali are in some way redemptive: she is just transported by love, and by her contempt for the thin-lipped gossips and bigots who disapprove. Yet their love is not easy, and cultural differences are not wished away as easily as that.

The performances of Brigitte Mira and El Hedi Ben Salem as Emmi and Ali are superb; they act with instant sympathy and charm and in their own way, they are the most purely lovable characters I have ever seen on a movie screen. When Ali tells Emmi not to think too much: “Viel denken, viel weinen” (much thinking, much crying) it is heart-rending. It is a triumph of intersectionality – as no one used to say in 1974 – and a triumph of love.