The Children's Hour: Elisabeth Moss (left) and Keira Knightley star as school teachers in 1930s New England.

Timeless terror is brought to the fore in THE CHILDREN’S HOUR, a punchy play set in a boarding school in 1930s New England and staring silver screen siren Keira Knightley and Mad Men star Elisabeth Moss.

THE CHILDREN’S HOUR

Comedy Theatre, Panton Street, SW1

HAIR-pulling, nail-biting, face-cradling agony!

The Children’s Hour brings the 1930s and all its narrow-mindedness to life – as a schoolgirl’s whisper spreads, triggering a chain of extraordinary events.

Karen Wright and Martha Dobie run a girl’s boarding school in New England, where they become entangled in the devastating story of deceit, shame, and courage.

Keira Knightley as Karen brings a celebrity-factor to the play that fills every seat in London’s Comedy Theatre, but she also upholds the audience’s expectations. The plot cycles through complex emotions that put pressure on an actress used to being able to “CUT” and redo.

But she masters the sensible teacher battling with boarding-school anarchy, skillfully plays the American wife-to-be on the cusp of achieving her dreams, and regresses tactfully within her character as a woman for whom things don’t turn out to plan.

Elisabeth Moss as fellow-teacher, Martha, artfully treads the fine-line of an ordinary lady of the times and a distraught belle who cannot fit in or find the beau who might correct her misguided ways. She makes her character - written to be controversial – as sensitive, anxious and human as possible.

But the show’s true star is Bryony Hannah as Mary - the calculating child with the power to destroy her teachers’ careers. So convincing is Miss Hannah in her manipulative role that you feel an unstoppable urge to “Boo” out loud when she takes her final bow. A striking choice for a character who knows not, nor wants to know, any better.

The timeless terror of this Lillian Hellman classic resides in the power of a word, and director Ian Rickson’s focus is perfectly concise with no extra fluff. Simple sets, simple costumes, and all the punch in the plot, superb!

* Showing at the Comedy Theatre in Panton Street, SW1, until Saturday, April 30.