The Promise review – high drama of Labour landslide collapses into argufying

The economy is in the doldrums and people are tired of being fed lies and propaganda by government. Then, a general election brings a landslide victory for the Labour party on the promise of wholesale change.

This scenario is not, as it may sound, about the here and now but a slice of British political history from 1945. Paul Unwin’s play begins as radical leftie, Ellen Wilkinson (Clare Burt, full of angry passion) urges her party to tear away from Winston Churchill’s wartime coalition. Clement Attlee’s government is voted in and the drama takes us into his cabinet.

There is Attlee himself, an uncharismatic leader (played with due lack of charisma by Andrew Woodall), and the scheming Herbert Morrison (Reece Dinsdale) who wants to oust him. Also among them is Nye Bevan (Richard Harrington), the Welsh firebrand who had his own drama, Nye, at the National Theatre earlier this year , and Jennie Lee (Allison McKenzie), the minister for the arts and Nye’s wife. Sitting somewhat at a distance is the outspoken, obstreperous Wilkinson, who has past form as a communist. Together, they must work out how to realise their promise to the people.

While this is an eminently honourable premise, it does not translate into gripping political drama here. Directed by Jonathan Kent, it is visually arresting and well performed but it is unclear for too long what and who it is about. The sparky chemistry between Bevan and Lee suggests it might be about them before the centre of gravity turns towards Wilkinson.

She speaks in political ideals but we learn little of her as a person. There is her affair with Morrison, but their bedroom scenes contain only more political debate.

The focus is the inner ideological wranglings of this government, with debate upstaging drama. Characters too often shout at each other, arguing out their positions on everything from nationalisation to health, education, borrowing to invest, India and Palestine.

Back screen projections of Attlee entering N0 10 and images of dining rooms feel rather too literal but Joanna Parker’s quickly transforming set, with its wheeled on/off furniture is stylish and slick otherwise, with a great sense of sound (from fireworks that hail a new political dawn to the clacking typewriters of the Labour party office).

Related: ‘A moment to create the country they dreamed of’: Labour’s 1945 landslide becomes a play for today

The play seems tacitly to pose the question of what happens when a government promising transformation takes the reins of power. Do its promises become diluted? We never find out.

It grapples with women’s outnumbered position in politics too, albeit briefly. Clement Attlee’s wife, Violet (Suzanne Burden), brings up Wilkinson’s unmarried, childless status, which rings of the “cat lady” comments of today , and reminds us that while much has changed, narrow perceptions of women in power remain.

The debates are all cogent, and sometimes dismally current, but as a piece of engaging political theatre it does not live up to its promise.

• At the Minerva theatre, Chichester, until 17 August