Constellations by Headgate Theatre Productions. Runs until Saturday, June 25, for tickets call 01206 366000

Nick Payne’s play explores the notions of multiverses, multiple- universes, where alternative events happen. It plays with the notion of those crossroads that we arrive at in our lives, where a single choice, a response, the word yes or no, can alter the path of our future. The genius of the play is that he does it through the multiple meetings and life events of just one couple, Marianne and Roland. Scenes are repeated and shown from different angles and outcomes, he is a beekeeper, she a scientist. It kept me on my toes emotionally and intellectually in this gorgeous production, performed by two outstanding actors.

In the hands of less skilled performers, this could have been a confused production, but Michael Cook and Charlotte Still perform each scene with commitment and subtlety, changing paths and characterisations with (seemingly) ease as they repeat, replay and change each outcome. In some versions she is unfaithful, alternatively he is. They split up, or not split up, in one universe he is not a particularly nice person, in an alternative it is she who frustrates and abuses the relationship. Just as the play runs the danger in frustrating the audience too much, (maybe it did for some people), Payne raises the stakes as her cancer diagnosis is benign in one version, but leads to her death in another. In that version, without being spoken out directly, she decides to fly to Switzerland to end her life, and his appeal for more time just at the point of departure is deeply moving. It is a beautiful play, and it was a privilege to watch their performances.

Skilfully directed by Ian Amos, his clear vision avoided confusion, and the excellent lighting design by Martin Rayner gave colour and meaning to each universe, and flickered beautifully from section to section. The play is a hive, each scene the honeycomb within, the actors the bees moving us from each alternative to the next. Astonishing work.

PAUL T. DAVIES