LEGEND has it that King Arthur will return to save England in its hour of direst need. Rory Mullarkey does not make explicit reference to that idea in his intriguing allegorical play St George and the Dragon, at the National Theatre. But his George returns to what he refers to as his “native land” to save us on several occasions, each with very different results.

I spoke last week, in writing about Zimbabwe, of our duty to maintain the narrative of optimism. If there is one in the reiterations of Mr Mullarkey’s George it becomes increasingly attenuated. He offers an interesting final conclusion, but I am leaping ahead.

In Act I, Sir George returns to England after winning his spurs as a Knight of the Brotherhood and engaging in his first quest: a fight with a dragon, who sees him off rather ignominiously. Our disheartened hero comes home in search of a quiet life, with a little patch of land, a goat or two, and perhaps a wife. But, of course, he finds that England, too, is now in thrall to a fire-breathing beast, whom he defeats after rallying the dispirited countryfolk to improvise for him some armour and weapons from their work tools and farming implements. The Dragon is vanquished, and George invites the people to envisage a brighter and bolder future.

In Act II, our hero, who is by now Saint George, appears at the height of the Industrial Revolution to find that the Dragon is now a cartoon personification of capitalism, grinding down the workers who built the brighter and bolder future which has not quite come to pass. This reptilian reincarnation is also defeated, thanks to the collective action of ordinary people.

But, by Act III, the inhabitants of Britain are entrapped in a globalised consumerist economy, distracting themselves with a boozy self-focused individualism. The returning George is bewildered by the fact that the Dragon has now entered the souls of the population; his evil has become internalised in them. The only hope in the play — in the written script, at least — comes at the very end, when a child repeats the invitation with which George ended Act I: that the people should close their eyes and think of a better future. (Disconcertingly, on the stage, this line is delivered by an adult — the woman whom George constantly strives to save from the Dragon.)

The play moves from innocence to experience, and then towards what an optimist might call grim resignation, or a pessimist would adjudge as despair at the ways in which human beings do not learn from history, and indeed seem, sometimes, to be incapable of doing so.

It is a flawed play, but its themes — Original Sin, and what the former Dominican theologian Matthew Fox called “original blessing” — tussle inside your mind for days after. Events such as those in Zimbabwe make them more vivid, but offer no real resolution. It took something else to hint at that. It is to do with the distinction between optimism and hope. But more of that next week.