I loved the music the black comedy and the dark realism of The Pacifist’s Guide to the War on Cancer. The presence of the voice of the author as a kind of narrator provided a useful distancing device, as did the nightmarish visions danced to the noisy grunge rock music. The performances were unstinting, the singing and dancing delivered with panache – and by halfway through I thought the show utterly brilliant. Characters were revealed in songs, some of which were beautiful, but then as the cancers spread around the stage there seemed nowhere new to go with the dark comedy and satire.

Shannon received the news that her unborn baby was clear of the genetic disease that was affecting her and had killed her mother, and she performed a beautifully executed but somewhat predictable tap dance of happiness. Others received less good news and the stories of real patients were overlaid on the speeches of performers. The frame began to collapse as the performers were pushed towards the audience by the growing cancer bean bags – and the author/narrator again intervened. This is where the performance lost me.

What had started as a black comic attack on the horror of cancer turned into a kind of therapy session incorporating voices and stories of victims and calling on the audience to become involved. Despite the characters commenting that one of the things not to do to cancer sufferers is to offer the ‘cancer face’ of sympathy the production moved into that territory in the final portion, remembering friends and family who had been lost to audience members. While I applaud the conviction of the performers, and can see that many audience members were genuinely moved, the moment the camp distance of black comedy and the nightmarish vision of a night on an NHS ward were left behind so was the potential to say something different and vital.

Although I had mixed feelings about this brave, flawed production I nonetheless applaud the National Theatre’s strategy of developing new approaches to musical theatre writing and look forward to many more such experiments.