Mary Stuart, Donmar Warehouse, London

Regal portrayal of a deadly feud

Lloyd's most audacious stroke is to maroon Elizabeth and Mary in 16th-century dress amid a mass of male courtiers in modern grey suits. Their sartorial isolation vividly highlights the common predicament of these rival queens. Both are prisoners, at the mercy of unreliable men - Mary literally so in Fotheringay castle; Elizabeth captive to her scheming advisers and to the popular will, in the no-win situation created by her Catholic opponent's presence.

The swift-paced production is brilliant at communicating both the grim comedy of the shameless politicking and faction-ridden intrigue at court and the sense that this drama boasts not one but two tragic heroines, whose antithetical journeys are mapped out here with a piercing clarity.

Janet McTeer's wonderfully charismatic Mary graduates from a tense, haunted guilt about her role in the murder of Darnley to a radiant, assured queenliness in the spiritual honesty and dignity with which she faces death.

Harriet Walter's splendid Elizabeth travels in the opposite direction. She starts out as a haughty, self-amused icon of regality, gorgeously apparelled in black and gold, and secure enough to dispense tart witticisms about the ironies of her situation ("To please my servants, I must take a master," she quips of the projected alliance with France) and dally flirtatiously with favourites.

By the end, though, as she tries to forge a damage-limiting solution to the problem of Mary, she has degenerated into a figure of desperate, face-saving denial and infinite loneliness. The paradoxes of her plight no longer seem so piquant. "Slave to my own free people. Oh appalling/ Servitude", is her caustic cry in the pensive privacy of a soliloquy.

The two divas intersect only once, in a climactic (if entirely apocryphal) encounter at Fotheringay. Again, Lloyd's directorial decisions are bold and entirely persuasive. She has the women meet during a heavy downpour of rain. You'd therefore expect that the sodden, dripping Mary, who has earlier been whooping with a child's delight at the release and fun of frolicking in a shower, would be at a grave disadvantage. These are not the most decorous circumstances for the summit that she has been rehearsing in her head for years.

Instead, you marvel at the way that, with the scales even more weighted against her, Mary still manages to seize the moral initiative, eventually erupting in a reckless lava-flow of scalding outrage. The abandoned, almost animal exultancy to which McTeer then magnificently gives vent is a tremendous indication that this woman has been liberated into a freedom that Elizabeth will never know.

Guy Henry is in excellent, slyly comic form as an effete, devious Leicester, who, charged with changing his position on Mary's execution, purrs: "That was justice. This is the national interest." Rory Kinnear makes a strong, unsettling impression as a dangerously infatuated Catholic convert. But then, the cast does not have a weak link. Schiller's star is still on the rise.

To 3 September (0870 060 6624)