The city of Metropolis appears with an opening montage - superimpositions of a gigantic machine of pumping machine pistons, flywheels, a rotating crankshaft, and an off-center disk - all parts thrusting, moving, pounding and turning. The 24 hour clocks in Metropolis have been redesigned, with only 10 hours on their dial. The work shift (divided into day and night of 10 hours each, in the 20-hour day) changes at the end of ten hours, signaled by steam whistles blowing.
Two parallel corridors contain two groups or battalions of uniformed workers (in dark worksuits) who are lined up in rows of six. The sullen workers leaving the subterranean machine area after their shift are exhausted, marching in unison only half as fast as the new shift of entering employees.
A cage-elevator takes the day-shift slave-workers down to their underground living quarters in the Workers' City - the cage sinks and the camera remains on the same level, but the inter-title credits that follow sink into the depths, dropping from top to bottom: Deep below the earth's surface lay the workers' city.
Three elevator loads of workers march toward the camera - a reverse angle shows them entering the main square of the Workers' City - a transit area where a giant gong is positioned. The next downward scrolling titles display a perfect triangle, pointing upwards: As deep as lay the workers' city below the earth, so high above it towered the complex named the "Club of the Sons," with its lecture halls and libraries, its theaters and stadiums.
The next scene is located at the airy, light, above-ground Sports stadium. In sharp contrast to the workers' area, athletic, virile youths, dressed in white, exhibit their liberation by engaging in a footrace around a track in a horizontal movement. The next scene occurs in the Eden-like Eternal Gardens, a pleasing, erotic place for the privileged youth to play and pleasure themselves: Fathers for whom every revolution of a machine wheel meant gold had created for their sons the miracle of the Eternal Gardens.
In an artificial grotto, with sculpted columns that rise like stalactites, young women in carnival costumes with head adornments frolic, while peacocks roam.
Ring-master: Which of you ladies shall today have the honor of entertaining Master Freder, Joh Fredersen's son?
He has one of the ladies twirl counter-clockwise, and then clockwise to display herself - she is topless except for a light gauzy covering. The main character, Freder (Gustav Frohlich), the young, pampered, (motherless) son of a ruling, aristocratic capitalist - the autocratic master of Metropolis, is introduced as he plays hide-and-seek with the ladies.
Around a circular water fountain partially hiding a water siren within its streams of water, the white shorts-wearing, ignorant and pampered Freder flirtatiously chases a young lady with a backless tight black top. When he catches her, bends her backwards, and presses towards her for a kiss, the frivolous scene is interrupted by the opening of doors from the medieval underground, to the gates of the futuristic garden above ground.
Emerging into the open air is a vision and apparition - a beautiful young woman Maria (Brigitte Helm) who leads and cares for a group of waif-like, hungry worker children. Freder is distracted by the virginal, motherly figure.
Maria (to children): Look! These are your brothers!...Look- - ! These are your brothers!
The ringmaster from the Gardens orders the intruders to be dismissed, although Freder has obviously been entranced and profoundly impacted by her - and clasps his hands over his heart. The foreign group are shuffled away and the door closes, but Freder remains intrigued while ignoring his other lady friend.
Freder: Who was that?
But is told nothing. The next caption reads: But this is what happened to Freder - son of Joh Fredersen, master of Metropolis, when he went in search of the girl. With his conscience stirred, Freder voluntarily enters the depths of the workers' realm. He runs through the doors in search of the girl - but comes upon the underground Machine Hall where the proletariat toils and suffers a miserable life.
He has entered a part of the factory where a giant machine (termed the M-Machine or Moloch Machine) with a monstrous crankshaft rotating at its center is manned by twelve workers attending to dials, blinking lights and other controls. One of the straining workers collapses from exhaustion, and the machine's temperature gauge (resembling a thermometer) rises dangerously high. It overheats and explodes, propelling men through the air and sending plumes of steam skyward.
When thrown to the ground, Freder hallucinates that the machine's center has become the Moloch creature with eyes, nose, Sphinx-like front paws, and a gaping maw into which the masses of workers, now stripped and bald, are fed. Symbolically, the Moloch machine's inexhaustible appetite consumes the human lives of its operators, who are whipped into submission and led up the stairs to their death.
Groups of dark-uniformed workers, in rows of six as in the shift-change sequence, march up the stairs in unison toward the mouth, as the Moloch monster is transformed back into the machine in Freder's eyes. Struggling and wounded workers (some carried on litters) move from right to left, in silhouette, in front of Freder, after the industrial accident.
Appalled by the horrors of the working world and the waste of life, Freder runs to a waiting limousine.
Freder: To the new Tower of Babel - to my father!
He is driven on an elevated highway through Metropolis, full of fantastical towering skyscrapers, airplanes, traffic on the city's crowded streets, skycars, bridges and arching or suspended expressways.
In ruling Master Joh Fredersen's (Alfred Abel) executive office, busy male secretarial assistants feverishly work at their desks, taking dictation notes and watching a board of changing numbers.
Freder first speaks to his father's assistant Josaphat (Theodor Loos) about his witnessing of the machine explosion, intent on telling his engrossed father about it. Fredersen sternly reprimands Josaphat for not keeping on top of the situation.
Fredersen: Why is it, Josaphat, that I learn of the explosion from my son, and not from you! The details!
He sends him off to investigate. The Master then sends away his secretaries, and reassures his son, but Freder is deeply affected by the tragedy - he grabs the sides of his head with his hands and sinks into an armchair.
Fredersen: What were you doing in the machine halls, Freder?
Freder: I wanted to look into the faces of the people whose little children are my brothers, my sisters... Your magnificent city, Father - and you the brain of this city - and all of us in the city's light. . . And where are the people, father, whose hands built your city?