Eddie Izzard puts Radar on the map.

Lacking the star-laden cast, salacious subtext and tragic coda of its theatrically released cousin, BBC TV movie “Castles In The Air” was always destined to be overshadowed by “The Imitation Game”. That’s a real shame because the BBC production is just as handsomely staged, just as fascinating and tells the story of a scientific breakthrough just as vital to Britain’s wartime efforts as Turing’s cracking of the Enigma code.

In the mid 1930’s with the clouds of war gathering over Europe, maverick meteorologist Robert Watson-Watt (Eddie Izzard) races against time and the scepticism of a stuffy establishment to prove that his theory of being able to protect Britain’s skies by detecting approaching aircraft using radio waves is not only possible but can be applied practically. With little support in the way of resources or manpower, Watson-Watt pulls together a handpicked assortment of fellow weather forecasters and set about creating one of the defining technologies of the war.

Izzard, often an unconvincing and self-conscious actor, does some of his best work here. It’s possibly a career best performance as the driven scientist despite an accent in which his stand-up fans will detect more than a hint of Mrs Badcrumble. No doubt the general anti-establishment tone of the piece appealed to him as his group of plucky working class boffins struggle against the arrogant and aristocratic Whitehall departments represented by David Heyman as Churchill’s scientific advisor Frederick Lindemann and Julian Rhind-Tutt (who really seems to have found his niche playing offputtingly sneery upper-class Englishmen) as Physicist Albert Rowe. Luckily, there’s Tim McInnerny’s ever so slightly caricaturish Winston Churchill to ride roughshod over procedural propriety and make sure Watson-Watt gets his chance.

Although a war time movie, “Castles In The Sky” feels, with its playful score, more like a tweedy version of “The Social Network” as the rag tag band of inventors earnestly work their way towards inventing Radar (and, inadvertently, microwave cookery) in time to aid the Battle of Britain.

Maybe it’s not quite cinematic in tone or execution but it’s a definite cut above the general standard of TV drama and illuminates an oft-overlooked story of innovation, ingenuity and determination at the very beginning of World War II.