A ripping good war film, We Dive at Dawn is a "must see" for those who relish submarine-based movies. Like many of these films, there's a certain formula that is adhered to -- introduce the fairly large ensemble, get to know them as basic types, pack them into the sub and start off on the mission. In some hands, this formula can lead to predictability and boredom, but Dive for the most part avoids this. True, the characters are essentially types, but the director and writers have added enough detail and nuance to make them stand out as more human. Director Anthony Asquith also seems to be fascinated by the mere workings of a submarine, and his attention to detail here adds energy to the depiction of typical life aboard the boat. These men are professionals, but -- unlike in a Hollywood movie -- they are not superhuman; they make mistakes, they misjudge, they do their best but sometimes their best may not be what is required. Asquith and his writers are aided enormously by a first rate cast, with special kudos due to Eric Portman and John Mills. Portman is excellent throughout, but especially in the climax, as he goes undercover to save the sub. And Mills, who could have played this part in his sleep, keeps things fresh and new. Dive has tension, excitement, and top drawer acting, writing and direction -- a classic of its kind.