The film convinces as a period drama, though some soldiers, who should look pinched and ration-fed, are well nourished and handsome. Yet the story works, with the action swelling like a wave, then suddenly delivering a slap in the face. From above, we see a pilot ditching his damaged Spitfire in the sea, and the procedure runs smoothly; later, another flier does the same, and we stay with him as he lands. A tumult of water rushes toward him and fills the cockpit at alarming speed, while he batters on the canopy above, which refuses to slide open. Smoothness, viewed from another angle, collapses into the roughness of panic. All becomes darkness and deluge. Humans turn into creatures of the deep. A pale hand flickers like a fish. The cast is overall strong, with Murphy giving a convincing performance, though not that long in terms of time.