Parallel cutting is a narrative device that reaches its maximum density in D. W. Griffith's Intolerance (1916). Griffith used the technique to construct four parallel, but thematically, related plot lines that all achieve climax in a single rapid-fire montage. This editing structure was first developed to create suspense: we see a hero rushing to rescue a damsel in distress -- the director cuts between the girl's peril and hero's efforts to save her, accelerating the editing rhythm to achieve a visceral sense of frenzied motion driven to a climax. In Intolerance, Griffith's four parallel plots themselves involve parallel montage within the individual stories -- for instance, one of narratives involves a man about to executed: we see this as a flurry of shots showing a car in which an officer carries a pardon, a train that the car is racing to an intersection, and the death chamber in the prison where the condemned man is being slowly led to the gallows. Will the car out-pace the locomotive and deliver the pardon in time to save the condemned man? This episode, cut to the frenetic rhythm of a surging locomotive, is itself interpolated with other narratives: Babylon falls, Christ is crucified, and the Huguenots on massacred on St. Bartholomew's Day. The fundamental paradigm for this kind of cinema is represented by a speeding locomotive roaring down a track to which a girl has been tied a mile or so away. Parallel cutting simulates a ticking clock, a sort of time bomb, or a locomotive churning forward toward a destination where either doom or a last-minute rescue will occur.
Christopher Nolan's Dunkirk is the most elaborate example of parallel cutting that I seen -- it's cubist complexity is on par with Griffith's Intolerance. The relentless score by Hans Zimmer is remarkably simple-minded -- the soundtrack either makes a chugging sound like a locomotive or ticks loudly like a watch or the timer-fuse on a bomb. Toward the end of the film, the soundtrack sounds a bit like the overture to Tristan and Isolde -- the music keeps surging rhythmically forward yearning to reach some kind of resolution but the cross-cut action on screen keeps delaying the score's final orgasmic climax. Intolerance is a monument in film history but it is rather cold, schematic, and it's elaborate structure holds the audience at a arm's length. Dunkirk suffers from the same flaws -- notwithstanding many spectacular sequences, the film is chilly, abstract, and, ultimately, so ingeniously complex as to be somewhat alienating. We don't really sympathize with any of the characters because they seem to be mere cogs in a vast assembly of interlocking gears -- the machine is remarkable and, when all of its gears are turning, even majestic, but we don't really care about the human components of the system. This is a valid approach to a war film in which, by definition, the actions of individuals are subsumed within a greater narrative -- but Nolan's complicated narrative strategies distance us from his characters.
Dunkirk involves three parallel plots that briefly coalesce and, then, come apart again. Nolan's innovation is to employ different time scales for the separate narratives. One story involves a civilian boat piloted by Mark Rylance that crosses the English Channel to rescue British soldiers trapped on the beach at Dunkirk -- this story takes place during the time of one day. The first story that we are shown in the film is called "The Mole", referring to the pier extending out into the Dunkirk harbor; this narrative involves two young men who wordlessly collaborate to try to survive the carnage on the beach -- "The Mole" is narrated across a period defined as "one week." (Titles inform us as to these time scales.) The third element of the movie involves three Spitfires and their pilots who engage German planes over the Channel in an attempt to keep the Luftwaffe from strafing the beaches or bombing the vessels surging across the Channel to rescue the besieged soldiers -- the narrative involving the pilots is suitably quick and bloody: it takes place across one hour. Nolan sutures these three narratives together to reach a climax in which the sole surviving fighter battles the last of the German planes over the beach while the little yacht piloted by Mark Rylance makes its way through maritime chaos, evades torpedos and bombs, and rescues the two young men who have been cast adrift from not one but, at least, two vessels destroyed seriatim by German fire. The movie remains unremittingly true to its schematic premise: we never see any of the action from the German point of view -- rather, everything is shown from the point of view of the trapped British troops, the soldiers flailing about in the water, and the fighter pilots engaged in desperate duels over the battlefield.
The film is a strange, daunting work of art, continuously compelling visually, and, sometimes, reaching great, torrential climaxes -- in one sequence, for instance, a downed fighter pilot is unable to escape from the cockpit of his plane and is drowning, Mark Rylance's little brown yacht is rushing to the pilot's rescue while German machine guns bore holes in a metal boat filled with desperate British soldiers and swamped in the high tide -- water shooting into the vessel's hold through the innumerable bullet holes. The soundtrack roars like a surging locomotive and the imagery achieves a certain visceral and savage energy that can't be discounted although the film's cubist design is exceedingly abstract. (The abstraction extends to the casualties -- the film spares us the gore and severed limbs typically portrayed in recent war films.) The beach at Dunkirk is visualized as a weirdly lonely and isolated place -- long lines of troops standing in the sand waiting to be strafed or bombed into oblivion, rows of corpses neatly resting in the scummy sea-surge. The air battles are exciting if a trifle repetitive -- Nolan uses a highly schematic system of images and edits in these scenes: a close-up of a hand on a throttle, a shot of the planes swooping through the air, a shot of rear of the enemy plane in the crosshairs, a close-up of the pilot's finger on the trigger, squeezing the trigger, and, then, tracer bullets shooting into the German plane and knocking plumes of smoke out of it. Nolan doesn't seek to vary this pattern and it repeats, at least, six or seven times in the movie -- obviously this is a conscious aesthetic strategy that characterizes the fighter plane narrative, but it's peculiar how rigorously the director cleaves to this image pattern. The ending of the film is spectacular, but, again, from a highly formal and cinematic standpoint -- the sole surviving Spitfire lands on the Dunkirk beach at sunset; one of the boys who has survived drowning about four times reads Churchill's famous speech about fighting in the fields and beaches and never surrendering (the speech is in a newspaper and the boy is on an evacuation train.) When the words about never surrendering are spoken, we see the pilot, in fact, captured by shadowy Germans -- the only time we see the enemy in the picture. The soundtrack suddenly resolves into the famous Nimrod theme from Elgar's "Enigma Variations" -- it's a stunning sound cue and comes out of nowhere -- and, as the music reaches its climax, we see the Spitfire burning on the beach. This should be the last scene -- but it's not: Nolan's final image is much more brilliant. The music stops and there is a single shot, only a couple of seconds long, of the boy-soldier who has survived the battle and come home: he looks up at the camera with desperately frightened eyes. For once, the soundtrack is silent and the film ends.