A no-frills propaganda piece put together by professionals. Captain Grant takes his submarine to the coast of Japan, where they slip through security nets to land a key information gathering team for US bombing raids. Along with the same year's British equivalent We Dive at Dawn, the blueprint for the sub-genre's laid out here, with depth-charge anxieties, underwater model work, rousing torpedo highlights and much banter among the mix 'n' match crew the order of the day. It's decently done, if perhaps at undue length, but Grant is obviously ill at ease with the straightforward macho heroics - he's far too urbane for crass dialogue of the 'Now they'll feel the sting from our tail!' variety.