Characteristics
The danger from the extreme pressure of deep water dives and the claustrophobic, cramped submarine quarters imbues films of the subgenre with a great deal of dramatic tension. To heighten this tension, these films often depict submarine commanders descending below "hull crush depth" to evade attackers. Films from this subgenre tend to feature dramatic scenes in which submarine-hunters try to destroy submarines with depth charges. A stock scene in the submarine genre film is the depiction of a grim-faced submarine crew waiting in silence as depth charges explode overhead and bolts fly out of bulkheads in the submarine (they are dead silent because sound carries extremely well underwater, and so even the sound of men talking on a submarine would be picked up by normal sonar on other ships). Modern (post-World War II) movies often add conflict between different enemies.
Also a typical feature in all depicted eras is the sudden switch from hunter to hunted; while stalking enemy ships or carrying deadly nuclear missiles, the submarine often becomes, within moments, the hunted victim of overwhelming attack, the crew fleeing for its collective life.
While submarine films do use dramatic battle scenes, much of the tension in these movies tends to be created using other devices, such as conflict between officers, a threatened mutiny, or life-threatening problems with the diving equipment or the engines/nuclear reactor. This sets this subgenre apart from its parent genre of war films, which tend to focus more on battle scenes.
Read more about this topic: Submarine Films