From the moment Rona Morison sweeps onto the Lyceum stage as a playsuit-wearing Mary Queen of Scots, it is clear that her performance in Glory on Earth will be a driving force throughout. Accompanied by a hissing, cackling – and occasionally singing – entourage, she recounts the story of Mary’s life: born in France then uprooted to Scotland, where she is given the challenge of reviving Catholicism under the grim countenance of John Knox, her Reformist adversary. Knox, played by Jamie Sives, serves to contrast everything Mary believes in. Indeed, Glory on Earth is a story based around conflict. Even the warm lighting used in Mary’s private chapel against the blue tones focused on Knox when he gives his sermons is used to emphasise two clashing viewpoints as they come to a head with reckless disregard for the other.

Which is why it is disappointing that, compared to the rest of the play, the actual dialogue between Mary and Knox seems somewhat anticlimactic. Although the powerful emotions conveyed in these confrontations keep them from dragging, moments with the court and the private soloquies of both characters are far more compelling, as they bring humanity to what could otherwise be abstracted down to simply an argument between a petulant teenager and a stubborn old man.

However, despite this, the play is undoubtedly a triumph. As well as addressing the dangers of holding one’s ideology too stubbornly – something that is relevant in the current time period, despite its vastly differing context – the hypnotic verse written by Linda McLean and chanted by Mary’s loyal followers creates an atmosphere that serves to trap the heroine inside her own thoughts, making the moments of eerie silence during the church scenes even more unsettling. The costumes allow the characters’ allegiances to be shown through their reversable capes, and again Mary’s motif of flowers and birds contrasts with Knox’s stark black coat. Finally, the set design – consisting of imposing archways that descend from the heavens when characters storm off or on – is deliberately ambiguous, allowing the audience to either embellish it with the grandeur of a royal chapel or strip it back to reformist simplicity.

Conflict, tension, and above all, humanity; through a powerful combination of excellent writing and near-flawless execution, Glory on Earth reveals the strength our convictions give us, and the dangers they pose. And although the story may be centuries old, it still rings true today.