Thomas Paine is one of history’s great propagandists, a British radical who fought against his countrymen over the issue of American independence and would willingly have done so again to promote the cause of post-Revolutionary France.

Trevor Griffiths, a veteran of the political Left, has long wanted to claim Paine as a neglected national hero. A New World was originally intended to be a film and the project magnetised the interest of Richard Attenborough and Tim Robbins before succumbing to industry politics.

Reconceived for the stage, it feels politically noble yet dramatically stunted. It’s a play of incessant exits and entrances, punctuated with big statements. For instance, at the heart of Tim Shortall’s design is a bulging golden globe, symbolic of the Age of Enlightenment’s opulence of opportunity.

The result is a history lesson. Its first half follows Paine in America, where he earns acclaim as a fiery political writer. In the second he is in France. There the revolutionary spirit seems more feral, and Paine, roughly 15 years older, now finds himself condemned for being moderate.

Dominic Dromgoole’s production is a mix of bold flourishes, closely worked incidents, picayune interludes and mess, amid which Paine’s character never fully comes to life.

Keith Bartlett’s playful Benjamin Franklin, who appears in the guise of narrator (complete with a deliberately anachronistic fondness for the wit of Groucho Marx), says Paine is “willing to put the truth before his own neck”. It’s in this heroic idiom — uncluttered by psychological complexity — that he is presented throughout. Even when Philip Bird’s Edmund Burke pronounces him “a living danger to all that’s sacred in human affairs”, we’re simply meant to applaud his iconoclasm.

Although John Light suggests Paine’s unmannerly, sardonic, dangerous qualities, his performance feels too modest, a few outbursts aside, and his accent wanders curiously.

There is decent work from others: Jamie Parker, whose multiple roles include Jefferson and Marat, and Dominic Rowan, imposing as George Washington. But James Garnon’s Danton is an overblown roisterer, all locker-room virility and garlicky charisma. And the important lines — those most freighted with political substance — are highlighted like the key arguments of a PowerPoint presentation.

“The world’s made for turning,” says Paine in one such moment and the play’s concern with facing up to tyranny is clearly meant to resonate today.

Yet the distaste for colonialism, monarchy and religious inflexibility is conveyed without subtlety — or indeed sufficient context — and in the end the most heartening theme of A New World is its insistence on the power of the written word.

Until 9 October (0844 579 1940).