The National’s festival of new drama for young people habitually fields an impressive roster of authors, and the biggest name this year is David Mamet. A great shame, then, that his snippet, valiantly essayed by the King’s School, Chester, under Emma Lucia’s direction, proves a crashing disappointment. The Vikings and Darwin is barely 15 minutes long, tediously verbose and stubbornly undramatic. It frankly feels as though Mamet had half an idea, scribbled it on a scrap of paper and decided it would have to do.

In the Cabinet’s underground Whitehall War Rooms in 1941, civil servants debate the psychology of conflict. If a soldier dreams of his own death and his dream proves prophetic, has he simply given up? Or does he, like a Viking called to Valhalla, charge into battle with nothing to lose? Is his choice between the two states of mind Darwinian, and can such theories be applied to nations at war?

The arguments are admittedly pertinent to modern warfare and particularly to terrorist suicide bombings. But nothing enlivens the dialectic. It’s extraordinarily ungenerous.

With Six Parties, the novelist and screenwriter William Boyd serves the South Thames College in London and the director Emma Keele better, though his lack of theatrical experience shows. In an unnamed African country teenagers get high, get drunk and attempt to get off with each other.

Dynamic movement sequences, choreographed by Karen Lowe, express the shifting hierarchy of class, skin-colour and sex appeal more excitingly than Boyd’s flattish dialogue. But Boyd does point up the ironies and contradictions of a country in political flux and its relationship with the West.

Here, the rich kids — black and white — plan to study at Oxford or St Martin’s; Femi, whose resolutely African name and accent mark him out among the designer clothes and cut-glass accents, is the “fixer” who brings them illegal booze and runs their errands, and has no hope of such opportunities. His friendship with this ruthless nascent new elite is illusory.

Yet with so much youthful talent and enthusiasm on display, both writers could have given the performers much more to sink their teeth into. As it is, they’ve been somewhat short-changed.

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