To label Rona Munro’s drama as a play about mountain climbers is to miss much of what this warm character study has to offer.

It does address the inevitable question of why climbers climb, along with the less obvious one of why they stop - if they do - but also turns its attention to the conflict between the two impulses as well as offering insights into the role and power of mourning and into when the past is to be held on to and when given up.

We begin with three climbers, the veteran Grizzly and the younger Dog and Gnome, and as the actors actually clamber and rappel around Miriam Buether’s stark white set, we recognise the mix of adventure and technical precision that attracts them to climbing.

When one of the youngsters is injured, the white set becomes a hospital, where Grizzly meets a nurse who is a grieving widow. Their connection helps Griz decide that it may be time to move on and stop climbing, but the woman is not ready for the parallel decision - to her, moving on would mean denying the reality of what she lost with her husband.

There are similar self-examinations and self-discoveries for all four characters, and in this Paines Plough production, you believe in all four - self-contradictions and all - and wish them all well.

An excellent cast is led by Garry Cooper and Jan Pearson as the couple with too much separate history to be able to change their lives too suddenly, and directed with insight and sensitivity by Roxana Silbert.