I’m sure there are Hitchcock experts out there who can correct me if I’m wrong, but I seem to recall that the genesis of North by Northwest (1959), the classic thriller written by Ernest Lehman and directed by Alfred Hitchcock, began with two images from Hitchcock’s imagination: A chase scene atop Mt. Rushmore and the crop duster chase scene. The latter is today’s Great Scene.

Thornhill looks across at the droning plane with growing suspicion as the stranger steps out onto the highway and flags the bus to a stop. Thornhill turns toward the stranger as though to say something to him. But it is too late. The man has boarded the bus, its doors are closing and it is pulling away. Thornhill is alone again.

Almost immediately, he HEARS the PLANE ENGINE BEING GUNNED TO A HIGHER SPEED. He glances off sharply, sees the plane veering off its parallel course and heading toward him. He stands there wide-eyed, rooted to the spot. The plane roars on, a few feet off the ground. There are two men in the twin cockpits, goggled, unrecognizable, menacing. He yells out to them, but his voice is lost in the NOISE of the PLANE. In a moment it will be upon him and decapitate him. Desperately he drops to the ground and presses himself flat as the plane zooms over him with a great noise, almost combing his hair with a landing wheel.

Thornhill scrambles to his feet, sees the plane banking and turning. He looks about wildly, sees a telephone pole and dashes for it as the plane comes at him again. He ducks behind the pole. The plane heads straight for him, veers to the right at the last moment. We HEAR two sharp CRACKS of GUNFIRE mixed with the SOUND of THE ENGINE, as two bullets slam into the pole just above Thornhills’ head.

Thornhill reacts to this new peril, sees the plane banking for another run at him. A car is speeding along the highway from the west. Thornhill dashes out onto the road, tries to flag the car down but the driver ignores him and races by, leaving him exposed and vulnerable as the plane roars in on him. He dives into a ditch and rolls away as another series of SHOTS are HEARD and bullets rake the ground that he has just occupied.

He gets to his feet, looks about, sees a cornfield about fifty yards from the highway, glances up at the plane making its turn, and decides to make a dash for the cover of the tall-growing corn.

SHOOTING DOWN FROM A HELICOPTER about one hundred feet above the ground, we SEE Thornhill running towards the cornfield and the plane in pursuit.

SHOOTING FROM WITHIN THE CORNFIELD, we SEE Thornhill come crashing in, scuttling to the right and lying flat and motionless as we HEAR THE PLANE ZOOM OVER HIM WITH A BURST OF GUNFIRE and bullets rip into the corn, but at a safe distance from Thornhill. He raises his head cautiously, gasping for breath, as he HEARS THE PLANE MOVE OFF AND INTO ITS TURN.

SHOOTING DOWN FROM THE HELICOPTER, we SEE the plane levelling off and starting a run over the corn-field, which betrays no sign of the hidden Thornhill. Skimming over the top of the cornstalks, the plane gives forth no burst of gunfire now. Instead, it lets loose thick clouds of poisonous dust which settle down into the corn.

WITHIN THE CORNFIELD, Thornhill, still lying flat, begins to gasp and choke as the poisonous dust envelops him. Tears stream from his eyes but he does not dare move as he HEARS THE PLANE COMING OVER THE FIELD AGAIN. When the plane zooms by and another cloud of dust hits him, he jumps to his feet and crashes out into the open, half blinded and gasping for breath. Far off down the highway to the right, he SEES a huge Diesel gasoline-tanker approaching. He starts running towards the highway to intercept it.

SHOOTING FROM THE HELICOPTER, we SEE Thornhill dashing for the highway, the plane levelling off for another run at him, and the Diesel tanker speeding closer.

SHOOTING ACROSS THE HIGHWAY, we SEE Thornhill running and stumbling TOWARDS CAMERA, the plane closing in behind him, and the Diesel tanker approaching from the left. He dashes out into the middle of the highway and waves his arms wildly.

The Diesel tanker THUNDERS down the highway towards Thornhill, KLAXON BLASTING impatiently.

The plane speeds relentlessly towards Thornhill from the field bordering the highway.

Thornhill stands alone and helpless in the middle of the highway, waving his arms. The plane draws closer. The tanker is almost upon him. It isn’t going to stop. He can HEAR THE KLAXON BLASTING him out of the way. There is nothing he can do. The plane has caught up with him. The tanker won’t stop. It’s got to stop. He hurls himself to the pavement directly in its path. There is a SCREAM OF BRAKES and SKIDDING TIRES, THE ROAR OF THE PLANE ENGINE and then a tremendous BOOM as the Diesel truck grinds to a stop inches from Thornhill’s body just as the plane, hopelessly committed and caught unprepared by the sudden stop, slams into the traveling gasoline tanker and plane and gasoline explode into a great sheet of flame.

In the next few moments, all is confusion. Thornhill, unhurt, rolls out from under the wheels of the Diesel truck. The drivers clamber out of the front seat and drop to the highway. Black clouds of smoke billow up from the funeral pyre of the plane and its cremated occupants. We recognize the flaming body of one of the men in the plane. It is Licht, one of Thornhill’s original abductors.

A couple of things. First, note how closely the movie tracks per the script, almost shot for shot. Hitchcock was known for blocking out his movies, every shot beforehand — this sequence supports that point. Next notice how well the sequence builds in tension — a flyover, another flyover only this one with machine gun fire, another flyover with machine gun fire, only closer, the mad dash to the cornfields, then a flyover with poisonous dust, the race to the highway and the approaching tanker, building to the climax — each event bigger than the previous. Finally, for all those screenwriting instructors who say that you can only write what an actor can act and a viewer can see, check this out:

Thornhill stands alone and helpless in the middle of the highway, waving his arms. The plane draws closer. The tanker is almost upon him. It isn’t going to stop. He can HEAR THE KLAXON BLASTING him out of the way. There is nothing he can do. The plane has caught up with him. The tanker won’t stop. It’s got to stop.

“It’s got to stop.” How can Cary Grant act that? How can a viewer see that? They can’t. This is a case of the screenwriter Lehman breaking free and providing some commentary on the moment, he is expressing what Thornhill has got to be thinking — and perhaps even what Lehman and Hitchcock hoped the viewer would be feeling: “My God, stop!!!” Lehman makes a ‘novelistic’ choice at possibly the most important point in the story. So if any of your screenwriting instructors tell you you can’t do this, just steer them to Lehman’s script. At the end of the day, who would you rather trust: Your instructor or a screenwriter who was nominated for an Academy Award for writing 5 times?

Here’s the movie version of the scene. The plane appears at 5:30 into the clip: