There isn't an atom of suspense in this tepid thriller about spying scientists. Indeed, the most exciting moments are the games of chess during which defector Stephen Murray passes vital secrets to Communist squire Alan Wheatley. There's a valiant attempt to put a sting in the tail, but only lab assistant June Thorburn fails to see through the slenderest web of deception. This was clearly a shoestring affair, but director Montgomery Tully hardly strained to make the best of a bad job.

Boris Turganev (Murray) is a Russian scientist who has absconded from a Communist prison in an attempt to achieve a better life working for the British. As Boris struggles to make his superiors believe he is there to work and not to spy for the Russians, an office romance blossoms that could put his mission in jeopardy.