There's still a strong early-talkie flavor in John Ford's World War I sea-chase picture. The film isn't really edited to the pace of dialogue-driven movies; many shots are held longer than seems right by modern standards. The idea, usually, is to show off the authenticity of Ford's location shoot at sea, including real submarines in action. The long takes give a sense of reality and scale. Ford enhances that feeling with a mobile camera that figuratively cranes its neck to see the crow's nest of the story's "mystery ship" -- an old-style schooner equipped with modern artillery, designed to lure German U-boats into firing range. In command is Ford's protege George O'Brien, whom the director made a star in The Iron Horse, though he's best known today as the star of F. W. Murnau's Sunrise. Murnau and Ford were Fox Film stablemates in late silent days and Seas Beneath retains much of the Murnau-inspired house style despite the transition to sound. Ford's conservative enough with camera movement to make moments when the camera takes flight special.
There's a simple but remarkable shot midway through the picture, when one of the mystery-ship officers (Gaylord Pendleton, the younger brother of present-but-unbilled Nat) awakens from a night's drunk on a Spanish island to find that his ship is leaving him behind, and that a German sub is readying to attack it. We see him watch the schooner from a city wall, a picturesque setting we've seen several times earlier in static shots. When the officer turns and bolts down a flight of stairs, the camera pivots to follow, achieving an almost 3-D effect.
The officer tries to redeem himself by sabotaging the sub's refueling, but only earns an honorable death. It's typical of World War I films of this era -- one year after All Quiet on the Western Front -- that the Germans themselves honor him by putting his body in a life jacket so his own crew can find him. The Germans of Seas Beneath are antagonists without being villains. Ford takes an equal-time approach to their preparations for battle, as if to show that they're just men doing their job, so to speak, just like the Americans. There's even a melodramatic star-crossed romance between O'Brien's commander and the German commander's sister (Marion Lessing), who acts as a spy on the island, pretending to be Scandinavian while speaking perfect English. Interestingly, Ford remains committed to the couple's romantic potential while maintaining their wartime enmity. Annemarie is forced into a lifeboat by the doomed officer's sabotage and is rescued by the mystery ship. On board, she does everything in her power to warn her brother and his crew of the ship's true identity and purpose. Again, Ford doesn't treat her as a villain, but makes clear that she's doing what any German patriot would do in similar circumstances. O'Brien himself recognizes this and offers her the prospect of marriage as an alternative to internment for the duration. She prefers to stand with her brother -- most of the sub crew is taken alive -- but leaves open the prospect of reconciliation after the war.
Seas Beneath starts unpromisingly with a lot of Fordian service shenanigans with lunkheaded comedy relief from Warren Hymer and others, while Nat Pendleton does everything in his power to call attention to himself, presumably with Ford's connivance. Here he is trying to horn in on his brother's impassioned tango with another German spy.
George O'Brien's understated authority as the commander keeps the picture from going full cartoon, as does its evenhanded attitude toward the enemy. The film benefits throughout from nice location photography and camerawork from ace cinematographer Joseph August. Toward the end, Ford develops some nice tension as the mystery ship takes a beating from the sub's guns without responding -- we're told the Germans prefer to use guns instead of torpedoes on small-fry like this -- in order to lure the skeptical German captain into the trap O'Brien and his own submarine colleague have set. It ends rather abruptly once the worm turns, and if anything Ford overcommits to reconciliation by sparing the main Germans and teasing further romance in the future. But overall Seas Beneath is a fascinating piece of work from that moment when war could be treated without propaganda, well after the imperatives of World War I and before the imperatives of World War II.