By locating her play Small Mouth Sounds at a silent retreat, American playwright Bess Wohl sets an interesting challenge for the cast, since most of the action is wordless.

The charming comedy, which premiered in the US in 2015, features six people who arrive at a rural retreat to undertake a week-long spiritual course run by a guru who still has some way to go on the transcendental front himself. During an introduction by the disembodied voice of the guru (who we never see), the participants – who are lined up on a row of chairs – are told that they mustn’t use their phone, eat food in their room, or talk, though they are welcome to swim in the lake (naked if they like). Oh, and they should watch out for the panther.

Sharon Millerchip, Jane Phegan, Justin Smith, Dorje Swallow, Amber McMahon and Yalin Ozucelik. Photograph © Robert Catto

It’s soon clear that the participants all have emotional baggage they are hoping to address. In his daggy shorts and battered backpack, Jan (Justin Smith) looks decidedly awkward when he first arrives, and later puts a clearly precious photograph next to his sleeping bag....