Martha is a self-employed offal butcher in her 50s living in small-town Germany in the 1960s. She is strong and independent, but lonely. Into her life comes Otto, a brutish factory worker who wants a woman but no commitment. Martha keeps a diary. It is full of absences. Otto makes no bones about the fact that a man needs "away matches". He taunts Martha for her lack of womanliness, comparing her to hormone-pumped Russian athletes: men masquerading as women so they can win medals. He resents the fact that she earns more than him, and that she loves her dog, whom he sees as a rival. This is a man who has nothing going for him at all. But Martha's need for him is all-consuming.
Franz Xaver Kroetz's bleak two-hander is an extraordinary, quiet play about impossible passion, the gaps between men and women, the fact that you cannot give yourself to another person without undressing and revealing your emotional vulnerability. The more Martha opens up, the more Otto retreats. As soon as he starts to care, starts to feel, he does a disappearing act.
It is a fantastic play, and it is terrific to see the West End embracing something more worthwhile than Mum's the Word or Cliff: the Musical. But in truth, this evening has nothing like the impact that the production had when it played the tiny Southwark Playhouse in London earlier this year.
There, the claustrophobic intimacy between the audience and the events on stage made the show an entirely different experience. You were there, nose-to-nose, when Martha skinned a rabbit or Otto striped off for a shower. It was like eavesdropping on other people's lives. Impressive though this production is, it is a stark reminder that the biggest problem facing West End theatre is the buildings themselves - and the Duchess is one of the West End's smaller and more sympathetic spaces.
It is, however, beautifully staged and acted, although Simon Callow's Otto may not be to everyone's taste. Otto is all strut and preen. There are moments when Callow is magnificent - for instance, staring into a mirror in fancy dress and mesmerised by the different self he discovers there - but there are also moments when you are intensely aware that this is an actor giving a performance. It is a big, showy, thespian, look-at-me tour de force.
Ann Mitchell, by contrast, is quiet and raw. While everything in Callow's performance is externalised, everything in hers is internalised. It is an X-ray performance that lets you peer into Martha's lonely, yearning soul.
Until May 24. Box office: 0870 890 1103.