Two women with completely different approaches to life, meet by chance one sweltering day in a leafy, airy, gracefully furnished hotel tearoom in Manhattan. Once childhood friends, they have not seen each other for many years until one of them recognises the other and a faltering reunion takes place.

They exchange the usual. Both are married with children, both enjoy the comforts of middle-class life, both could pass for white, and for one of them her life depends on it. Things take off from there.

The riveting fact is that one of them, Clare (Ruth Negga), has been living her life as though she were invisible or white, yet both she and Irene (Tessa Thompson) are Black American women. In an impossibly blonde bob with bleached eyebrows, Clare might actually barely pass as white, but perhaps the point is here that majority opinion in the north of the US during the 1920s could not imagine she would not attempt to do so, unless she were.

Clare's husband, John (Alexander Skarsgard), a wealthy man whose offensively racist views are soon aired, certainly doesn't. When he meets his wife's childhood friend, he appears to have no inkling of her race either.

At first glance, the flirty, vivacious, seriously compromised Clare appears the more diverting character who is attractive to one and all, even, as is suggested at various times, her old friend. She makes an imperious order for "a pitcher of iced tea in champagne flutes" that the waiter duly brings, she's a party girl who can get away with most anything during the fluid, dangerous days of the Jazz Age.

It is Irene who is, however, the much more complex, and possibly more conflicted. She shows little interest in building on the chance encounter, but Clare shows up one day on the doorstep of her house in Harlem, the home she shares with her Black American doctor husband, Brian (Andre Holland), and their two Black American sons, whom she tries to shield from news of hate crimes and racism.

Courtesy does not allow Irene from rejecting Clare, but the woman's presence brings out a nervy, prickly side to her personality that seems to have been masked. Just what Clare represents for Irene, is one of the film's conundrums.

The book of the same name by Nella Larsen that this film is based on, was published in 1929 and apparently received with interest, but not much beyond New York City. Now part of the African-American and feminist literary canons, it is apparently faithfully reproduced here by British actor Rebecca Hall in her first directorial role.

In fact, in the background of this film about "racial passing" there are two more women of mixed-race. The writer-director Hall, daughter of theatre director Peter Hall and mixed-race opera singer Maria Ewing, is of mixed-race background, as was the novelist Larsen herself.

The film's two lead actors, Thompson and Negga, deliver nuanced, expressive performances that give voice to the powerful personal emotions underlying the narrative.

From lustrous black-and-white cinematography, sometimes drifting dreamily in and out of focus and always intimately framed in 4 by 3 by Eduard Grau, the film's approach to the novel is reverential. It is a joy to watch. Tinkling notes of jazz piano complete the atmosphere of a heaving city outside the door, buzzing with the jazz age.

Travelling shots that recur along the street in Harlem where Irene lives are one of the film's structuring motifs. Within the home where much of the action takes place, it is a women's world of softly textured 20s fashions, traditional household interiors and the engine-room of Irene's home, the kitchen where her Black American maid is hard at work.

Outside the home, Irene is involved in voluntary work for the Harlem community league, though little is heard about it. Glimpses of other sides of her personality are expressed in fascinating glimpses of her independence like the ability to drive and an occasional cigarette. Yet Irene's character remains an enigma.

No doubt the metropolis allowed for ways in which to recreate oneself, just like Gatsby. "Pass if you can, why wouldn't you?" The views are so at odds with perspectives of today but Passin is a fascinating, if frustrating, exploration of life in New York a century ago.