Who knew Terence Rattigan was Britain's answer to Betty Friedan? Carrie Cracknell's extraordinary re-reading of his best play, The Deep Blue Sea, makes it so. While Friedan argued America's housewives spent the 1950s trapped at home with their gleaming white goods, Cracknell suggests that Britain's, no less starved of love and purpose, had to contend with rationing and post-war austerity as well. Helen McCrory makes Hester less a woman who gambled stability for happiness and lost, than a waif with no life of her own, surviving on scraps of affection, plumbing the depths of despair.

With a single snick, Cracknell turns the play on its head, shifting any blame from Hester herself, who has left her husband for a younger, more passionate man, to the social structures in which she swims – or, rather, in which she drifts and drowns.

Usually, Hester is besotted with her boyish new beau, Freddie Page (Tom Burke), driven over the edge by his detachment and his drinking. His missing her birthday triggers the suicide attempt that famously starts the play – often played as a melodramatic attention grab. Here, however, she is stuck in a relationship gone stale – deeply, flatly unhappy – but better that than being a woman alone.

Instead of the usual tempestuous affair, passionate clinches then cutting rejection, their relationship has lost all its heat. Freddie, damaged by his wartime experiences, rations his tenderness to the occasional touch, and Hester mostly drifts around their flat like a ghost, abandoned and empty. She doesn't feel too much. She feels too little.

McCrory also suggests, radically, that Hester is still deeply in love with her High Court Judge of a husband. Instead of the usual old crone – in Terence Davies' film, Rachel Weisz swaps Simon Russell Beale for Tom Hiddleston, obvs – Peter Sullivan's Sir William Collyer is a suave, intellectual sophisticate, cutting a dash like Cary Grant. Hester warms up whenever he rocks up, protesting her love for Freddie to seed his jealousy and pining for the status of her past, but she knows, fundamentally, that their marriage was her prison; that she sought something else for good reason. When he proposes reconciliation, she refuses in spite of her heart.

All this puts the most brilliant backspin on Rattigan's play, giving every line a fresh subtext. Cracknell's production is both clear-sighted and complex, and McCrory is astonishing – brittle but resilient, and still capable of putting a brave face on. A dishevelled doll with bird's nest hair, she floats through the play, slower than everyone else, as if in the grip of an out of body experience. At times, she seizes up entirely, freezing in dissociation.

It chimes with a beautifully atmospheric production – an extended ache of a show. Peter Rice lets the dreamy harmonies of The Flamingos' swim through it, and Polly Bennett's movement adds the poise and precision of dance theatre. Tom Scutt's design – its translucent walls a mark of the lack of privacy – makes an ocean of Hester's flat; lace curtains rippling like surface water; kitchenette shadowy as the sea bed. There's strong support from Nick Fletcher as a kindred depressive spirit and Marion Bailey as a bustling busybody, but this is a revelatory revision of a classic; a feminist reading that proves Rattigan was miles and miles ahead of his time. Essential.

The Deep Blue Sea runs at the National Theatre until 21 September.