Helga is a young single lady who has a baby by a much older married man. After the older man tells Helga's father that he refuses to pay child support because he isn't the child's father, her father insists that Helga take him to court. On court day, just as the older married man is about to swear on the Bible that he is not the father of Helga's child, Helga suddenly tells the court that she's dropping the case because although the man did father her child, she doesn't want him to commit perjury, which is not only a serious crime but a mortal sin as well. Based on a 1913 novel by Selma Lagerlöf.
It was the first in a series of successful Lagerlöf adaptions by Sjöström, made possible by a deal between Lagerlöf and A-B Svenska Biografteatern (later AB Svensk Filmindustri) to adapt at least one Lagerlöf novel each year. Lagerlöf had for many years denied any proposal to let her novels be adapted for film, but after seeing Sjöström's Terje Vigen she finally decided to give her allowance.