Certain plays are easier to admire than to love. Danton’s Death (1835), written by Georg Büchner in a fit of revolutionary zeal when he was just 21, indubitably falls into this category, renamed as it is by some Danton’s Deathly.

The National has done its best to render this daunting political tragedy accessible, furnishing it with a top-billing leading man (Toby Stephens) and front-rank director (the Donmar Warehouse’s Michael Grandage, making his South Bank debut), but it remains a tough ask.

Büchner’s original text is sprawling and dense, threaded through with knotty classical allusions and punishingly long speeches. It’s the sort of play whose footnotes threaten to be longer than the work itself. Thank heavens, then, for this comparatively pithy, pared-down new version by Howard Brenton, presented as part of the National’s Travelex £10 season.

Brenton makes it clear from the start — as Büchner doesn’t — who’s who and who’s for which faction in the bloody aftermath of the French Revolution. It’s the spring of 1794, the Reign of Terror is raging and those former allies in the overthrow of the monarchy, Danton (Stephens) and Robespierre (Elliot Levey) are on an inexorable collision course. Danton, a man with a well-developed love of life’s earthier pleasures, wants to stop the purges and show mercy. His unbending rival is adamant the guillotine must still be fed.

The fate of France is discussed, at length, in a succession of nigh-on identical scenes that unfold in dark rooms illuminated by the occasional shaft of sunlight. An atmosphere of one-note portentousness threatens to settle, which Grandage partially disperses via the lighter, warmer episodes of Danton’s womanising.

On this evidence, it’s surprising these men had time to do any Revolution-ing at all, such is the speechifying they have to get through. Stephens is a weary revolutionary, most convincing away from the dry rhetoric of politics. “We had some times, body, you and I,” is his poignant reminiscence with himself on the eve of execution. He’s well supported by Barnaby Kay as Desmoulins, Danton’s loyal right-hand man.

Levey’s nicely pitched performance readily explains Robespierre’s nickname of the “Incorruptible”. His mean, reedy delivery allows no compassion or compromise, although Levey cleverly suggests a man who is increasingly haunted. His time at the top of Fortune’s wheel, we readily gather, will be short. The Revolution will eat itself.

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