The Observer’, Matt Charman’s powerful play about elections in sub-Saharan Africa, has been playing at the National Theatre during an interesting time for democracy. At the European Parliamentary elections, barely a third of voters in this country bothered to turn out, allowing the odious British National Party to secure two seats. Meanwhile in Iran, we are told almost 90 per cent of the electorate showed up to enthusiastically make their mark for the controversial incumbent or his reformist opponent. As in Charman’s play, we are reminded that democracy is not simply something the West can teach the rest – not entirely, anyway.

Fiona Russell, played by Anna Chancellor of Four Weddings fame, is the earnest and diligent deputy head of an election observation mission in an unnamed former British colony in Africa – so earnest and diligent, in fact, that she is passed over for promotion in favour of a clubbable time-server. The role of Russell and her colleagues is to observe the country’s first steps on the road to full democracy, not to interfere – something she asserts early in the play. But when her favoured opposition candidate looks close to losing, the observation team strays into the problematic territory of actively lobbying for a full run-off election between her man and the president – briefing western journalists, arguing with the country’s top judges and, when the incumbent decides to concede defeat, negotiating his possible immunity.

Here lies the moral predicament at the heart of the Western – perhaps especially the British – relationship with Africa. “We are here to help them,” Russell says at one point, in a phrase capturing a fatal lack of clarity – what exactly does that mean? Her complicated relationship with her clever and idealistic local translator, Daniel Okeke – admirably played by Chuk Iwuji – stands as a broader metaphor. The West treads a razor-fine line between hopeful encouragement and patronising interference. But Africans like Okeke are hardly blameless; early in the play he admonishes Russell for failing to go beyond her responsibilities and keep a polling station open beyond the permitted time, but later he rebukes her for following the logical progression of his advice and continuing to interfere.

Surreptitiously watching all of this is James Fleet’s sinister, linen-suited Foreign Office official, Saunders – a kind of malign ‘man from Del Monte’, charged with discreetly monitoring Russell’s actions. Why? To ensure she doesn’t get in the way of the British government’s agenda. Saunders, who’s been “bollocked off” to serve the rest of his diplomatic career in this, one of the more obscure African countries, is himself a kind of observer – though with rather fewer scruples than his compatriot Russell. Her earnestness may have the smack of patronising paternalism, but his scheming is much more troubling.

As with most National Theatre productions, the play is impressively staged, making the most of the space in the Cottlesloe – the smallest of the NT’s three auditoriums. It can tend towards the didactic, but its central message is worth hammering home – that good intentions alone do not a democracy make.