Engelein is a comedy of deliberately mistaken identity. If Jesta, a 17-year-old, can play the part of a 12-year-old, her family will gain a large inheritance from a rich uncle from Chicago. Her unruly “play-acting” for the uncle is preceded by an earlier incident in the film that results in Jesta being evicted from her girl’s school. Wearing a long, woman’s skirt, she climbs up a ladder and onto a thatched roof. She reaches over the top of the wall to kiss her boyfriend, who appears from the other side. However, Jesta is caught by the headmistress, and her forced descent is precipitous. Pulled downward, she reveals a great deal of a black-stockinged leg. She looks distinctly sexual as she falls into the matrimonly arms of the law, whose duty is to enforce the rules of female decorum.

After the revelation that Georg has seduced her, Maria is driven away by her father. Georg, fearing the wrath of Maria's father, has swiftly abandoned the girl and left for the mining town of Sankt Anton, where he expects to hide easily amongst the large population of colliers. Maria must care for herself, and ends up in Sankt Anton, where she attempts to rebuild her life. There, she gets to know Thomas, and soon the young people are engaged. When Georg and Maria meet again, drama ensues.