Nina Raine’s third full length play – and she really is establishing herself now — Tiger Country is touted as a theatrical antidote to television hospital soaps like Casualty and Holby City, but it works best when it develops, in the second act, precisely the same sort of narrative threads in the busy onrush of a hospital stretched to the limit.

A bullying registrar from Bhopal, Vashti, is pulled up short when her elderly aunt is mistreated for fluid round the heart. The new doctor, Emily, finds her boyfriend slipping away as she gets caught up in a pitched battle between medics and surgeons. And the cynical doctor John is suddenly confronted with his own bad news diagnosis.

At first, Raine’s own production is a tumultuous, occasionally inaudible hubbub in a drastically reconfigured auditorium with an acting area as big as a football pitch, scratchy projections of indecipherable operations, two pairs of swing doors and a babble of activity familiar to anyone crossing a hospital threshold.

But you’re gradually drawn into what is a meticulously researched and totally absorbing work play. Raine doesn’t glibly enter the recent (to most of us, incomprehensible) squabbles about NHS reform, nor does she aim to construct a “state-of-the-nation” metaphor, though some of the exchanges have the cutting edge and packed anger of David Hare’s dialogue.

Instead, she articulates the politics and rivalry in hospital corridors, and the drama. There’s a wonderful scene where two surgical teams await in silence the patients’ arrival in A&E, calm before storm: one is an “arrest”, the other an accident, and both cases illustrate the truth of two observations: surgery is about slabs of meat on a table; and, as a doctor, you can’t be a perfectionist in a hospital.

On the way, we have informative insights into testicular surgery, cardiac procedures, cancer treatments and the sheer physical grind and pressure of the work we all benefit from, even when nothing is ideally organized and no-one agrees on what happens next (as a patient, you just thank God for anaesthetics).

Raine’s production, designed by Lizzie Clachan and lit by Rick Fisher, has especially sharp, energetic performances from Thusitha Jayasundera as the insufferable Vashti, Ruth Everett as the ebullient Emily, and Adam James as the “get used to it” doom merchant, John; but this is a superb ensemble event, with notable contributions, too, from Tricia Kelly, Nicolas Tennant, Sharon Duncan-Brewster and Pip Carter.