Soaked in drink, riven by personal politics, surrounded by deceit, jealousy and ambition, the characters act out their complicated lives like passengers on a ship doomed to flounder on a reef and sink. And sink spectacularly some of them do again and again and again. Here are the tensions which keep us on the edge of our seats from the start to the end, helplessly watching, eager to offer advice, fearful of the consequences.

The situation is complicated by the myopia of the British – the natives are there to serve their masters and nothing more - the outdated hierarchical structure of manners - you may only address someone higher up the social ladders once they have spoken to you - the feeling that nothing that happens outside the compound fence is of any consequence, and the automatic assumption of the superiority of the British as a birthright.

Into this pressure cooker atmosphere, a sensitive boy finds the traumas of approaching adolescence are unfairly loaded. He grows up fast, and, astonishingly, at the end, emerges whole and, apparently unscathed. One can make this assumption knowing that this beautifully observed film is semi-autobiographical and that the maker, Richard E Grant is the living proof. Perhaps the telling of his gruelling story with humour and candour and its slow germination into film was a catharsis.

The period – Swaziland just before independence, a thousand years different from today - has been exquisitely created –– yet never feeling like a museum-piece.

Detail is immaculate, as indeed it must be in order to convince us. Everything from the clipped speech and floral interiors, to the rose garden desperately attempting to graft a tiny bit of Britain onto the alien soil, to the manners which seem so mannered, to the dresses, suits and diplomatic regalia of military white, gold braid and medals: everything is perfect.

It is all in the writing. We believe in the characters and feel for them even when their problems seen from the outside are self-inflicted, and no matter that their crises are sparked by shallow and shabby, selfish and petty ambitions. We have been there, and, little as we like to admit it, we see ourselves. Grant has a light touch. One smiles and laughs throughout. At moments, we cry.

Above all it is the minor characters who support the others who give credence to this film. Each has been painted as an individual never just one of a crowd. A thrill, here, to see, Caroline Smart with her name in lights at the end.

All this makes for a film that is delicious and plausible and heart-rendingly tender.

A superb performance from Nicholas Hoult as the youth growing into manhood, as well as from Julie Walters, Miranda Richardson, Emily Watson and Gabriel Byrne. – Andrew Verster