What if? is a fascinating game to play. The difficulty comes in making it credible. But that’s what Ivan Cutting’s new play for Eastern Angles succeeds in doing. The basic premise is a simple one – this country has failed to evacuate its army from Dunkirk in 1940, lost the Battle of Britain, evacuated the government to Canada and is now part of the German Reich (Scotland having become a Vichy-clone. It couldn’t possibly have happened? Think again.

I was brought up in Nazi-occupied Jersey, and so many details of Cutting’s script and Naomi Jones’ direction rang truth bells for me – curfews, reprisals, deportations, illegal crystal-sets and that thin fragile tightrope between keeping-head-down conformity and collaboration among them. But here we’re in Suffolk, where there really were plans for a guerrilla sabotage movement, as Cutting’s research has uncovered.

The action revolves around Diane, whose doctor husband is in a PoW camp, her deceased sister’s son Wilf and her other brother-in-law Tom, a retired army officer. He’s in charge of the local Auxiliary Unit, to which he’s recruited game-keeper Frank. Prue is an ATS wireless operator, billeted on Diane. For teenage Wilf it’s all something of a lark. Prue likes to flirt. Their elders, however, know well that this game is one with a particularly unpleasant death as its most likely outcome.

Fabrice Serafino’s set is a clever one with an underground bunker lowering the more domestic foreground. And the performances are also very good. Frances Marshall has real dignity as Diane, who survives, and Phil Pritchard is credible both as Frank and his replacement Alan, a man with a not-so-hidden agenda. Fred Lancaster plays eager-puppy Wilf, so brutally tossed into adult concerns and emotions. Tom has a certain ambiguity as well as authority about him, and this comes over clearly in Matt Addis’ portrait.