As a sort of Stroszek (1977) of its time, albeit by no means nihilistic and pessimistic in its concluding message, The Prodigal Son centers around protagonist Tonio Feuersinger (Luis Trenker), an adventurous Tyrolean logger and mountaineer who travels to the United States to climb the American Rockies, but he never quite gets there as the merry mountain-man's innate romanticism is to overwhelming for his own good and causes him to have a delusional vision of the supposed land of the free and home of the brave. While also inspired by the idiom “he who never leaves never returns,” to the dismay of his faithful lady friend Barbl Gudauner (Maria Andergast), Tonio also has his Tyrolean Teutonic eye on wealthy American beauty Lillian Williams (Marian Marsh) – a cosmopolitan lady more Aryan in appearance than his Tyrolean sweetheart – thus making for a secondary reason for leaving his small village. Far from the sort of negrophiliac barbarian typical of modern Hollywood action heroes with no sense of comradeship, Tonio is an old school male who takes pride in his hard work, even while working on Saturdays and singing the verse, “The merriest folks are the woodcutting folks,” while jollily busting his ass with his logger compatriots, as well as playing a fair good game of roughhousing with his friends. Tonio also puts family first above all else, finishing the work of his father (Eduard Köck) so as to help the old man with work that is getting harder and harder to do as he ages. A dual sun-worshipper and spiritual son of a Freyja-like Virgin Mary, Tonio has no idea that he is going to land on a virtual hell on earth full of beggars, degenerates, and racial mongrels of the superlatively American ‘melting pot’ sort. While dreaming of traveling to America and New York City, Tonio speaks too soon when he states, “God, I imagine living in a city must be a hundred times more beautiful than here,” as he feels like a “caged fox” and claims he does not, “like the mountains anymore,” but then again, as a son of the sun and blood and soil, the especially enthusiastic Aryan adventurist has yet to experience the distinctly inorganic manmade realms of crime-ridden cement metropolises of misery, which contain no natural beauty, free natural resources, or earthly adventure, but are instead teeming with distinctly human social abstraction and alienation, poverty and starvation, and rampant yet outlawed vagrancy; the sort of story that can turn a healthy farm boy into an HIV-positive tranny in no time.
When Tonio arrives in NYC, his senses are overwhelmed as he is bombarded with a curious cosmopolitan cocktail of pollution, claustrophobic atmosphere, stylistically sterile skyscrapers that block his view of the sky, unemployed Negros and other racial groups he has never seen before, pawn and cigar shops, and the endless lines of cars in traffic, which is in stark contrast to the relatively quiet and wide-open area of his mountain village where one need not worry about having too little personal space. Although he intended to meet up with the wealthy benefactor Mr. Williams (F.W. Schröder-Schrom) – a man who funded the prizes for a local ski competition in his hometown and would have provided the young man with financial security had his resources run dry – Tonio soon learns that the man is away for the winter, thus he must fend for himself without a dime to his name in a foreign city that eats people and spits them out in no time. Out of desperation, Tonio pawns all his belongs for a mere $1.50 and resorts to sleeping on park benches, where he is hassled by local police. Eventually, the Germanic immigrant finds work at dangerous job doing welding on a skyscraper in scenes that have a startling resemblance to the iconic photographs of American sociologist/photographer Lewis Hine, and, needless to say, Tonio is soon daydreaming about taking a boat back to his hometown. Despite working hard for virtually nothing, Tonio begins to resemble a degenerate drunken hobo of sorrowful sorts and even resorts to the previously seemingly unthinkable by stealing food and standing in foodlines, which a local police officers catches him for, but lets him go out of compassion for the immigrant's decidedly destitute state. Tonio ends up making one mere friend, Jimmy (Jimmie Fox) – an off-white Italian/Jewish type funnyman, not unlike a character from an early Fellini film like I Vitelloni (1953) – who is constantly in trouble with the law, but someone with whom down-and-out Tonio can identify due to his equally degraded and despairing position in American society. Eventually, by happenstance while interfering with a boxing match, Tonio becomes a successful prize-fighter and hooks up with wealthy Mr. Williams finally, even making his friend Jimmy successful in the process, but Tonio ultimately longs for the place of his birth and having experienced everything America has to offer, decides to go back home, where he is crowned the “Rauhnacht King” during the ancient Germanic pagan celebration of Rauhnacht where all the spirits rise from the earth (meadows, fields, fire, wind, etc.), in the from of the locals dressed in eerie and phantasmagorical costumes and masks, to worship the Sun-God, whereupon he is given the opportunity to choose between 12 Raunhnacht girls wearing masks to be his wife.