”Not the film”, shout the posters in the foyer of London’s wonderfully kitsch Cinema Haymarket. Even if the late1920s cinema does seem the perfect venue to show David Lean’s weepie, the posters are a deadpan reminder to audiences that no, this is not the 1945 classic, and no, you are not even seeing a film. Emma Rice’s adaptation is a theatrical piece in its own right, though being indebted to the film, comparisons are inevitable.

Most of us know Brief Encounter in one sense or another, it’s so ingrained in British culture. Scripted by Noël Coward, adapted from a short play of his, it tells the story of Laura, a housewife who goes shopping in town every Thursday. While waiting to go home at the station, she meets Alec, a doctor, like Laura married with children. Delicately but quickly, they fall in love, meeting at the station’s refreshment room each week. This being 1936, and this being Coward, it is all suppressed emotions and clipped sentences, as the lovers realise they must separate to preserve their other loved ones (“Self-respect matters, and decency,” reasons Laura). Such un-21st-century sentiments mark Brief Encounter as a period piece, in some ways easy to send up. However, it is also a classic love story, so it is not surprising someone has brought it back to its theatrical roots.

The story as the Kneehigh Theatre group tells it remains unaltered from the film: a series of flash-backs after Laura, exhausted, has returned home from being “a long way away”. But the treatment is something else entirely. Rice makes full use of her unusual location, mixing screen projections with stage action; she also has live musicians providing the score, with actors singing a soundtrack of Coward songs. It is not a musical; more, in its mixture of dialogue and song, a nod to the original writer. It seems appropriate to blend the flair for melodrama that Coward shows here with a song-writing talent that could conjure up the bawdy, the droll, or the elegant, such as This Misery Can’t Last (“This can’t last/This misery can’t last/Nothing lasts really/ Neither happiness nor despair/ Not even life lasts very long”).

But this does all make for a hybrid. And inevitably for a show using so many theatrical conceits (duets between filmed actors and live ones, puppets, even movements verging on dance as characters act out their emotions), some convince more than others. Strangely for a play shown in a cinema, those moments making exclusive use of the screen seem the least interesting. Suddenly, a two-dimensional screen can’t compete with the vigour of the action on stage.

Naomi Frederick and Tristan Sturrock do an excellent job of dispelling the ghosts of Celia Johnson and Trevor Howard as Laura and Alec. They give flesh and blood to characters stuck in a certain era, weighed down by the pressures of 1930s society, and some awfully English accents.

They are ably counterpointed by a gallery of comic characters who frequent the refreshment room. These interact with the audience, providing a steady stream of laughs – especially Amanda Lawrence, who, as the tea maid, Beryl, and a clutch of other roles, lights up the auditorium. This comic backdrop could, instead of complementing the sadness, overshadow it; but somehow, this show, silly, motley and stylised as it is, builds an emotional punch.

Lean’s film is marked from the first by Laura’s forlorn voice-over and Rachmaninov’s Piano Concerto No 2. Rice takes a different approach. At first, there is no sign of Rachmaninov, but instead the persistent strumming of a chirpy ukelele. But Rice plays a clever trick by waiting until the crucial moment before “unleashing” the concerto, and then using it one last time, at the end, poignantly.

Through such theatrical flourish, despite the copying and pasting, she makes this her own piece. And one in which, though the adaptation may be unorthodox, the emotion still rings true.

Cinema Haymarket, SW1

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