The five Selambs siblings have suffered the death of their mother and the incapacitation of their father, and consequently are left to fend for themselves, apart from the occasional check-in from both their guardian and the appointed manager of their ancestral estate. Perhaps unsurprisingly, none of them emerge unscathed from this upbringing, although the damage manifests itself in different and unforeseen ways. As they each attempt to forge their own path through the ranks of fin de siècle bourgeois Swedish society, it becomes apparent that none of them can escape the family traits of egoism and a desire for money regardless of ethics.

In this bildungsroman with five subjects, Siwertz charts the societal and cultural changes he observed during his own adolescence and early adulthood in Stockholm and the surrounding areas. Downstream (titled in the Swedish original simply as Selambs) is perhaps his best known work from a broad corpus of novels, short stories, poems and plays, and has remained highly regarded. Siwertz himself became part of the Swedish literary establishment later in life, as a member of the Swedish Academy and the Nobel Prize for Literature committee.