The Jungle tells the brutal reality of industrial Chicago in the early 1900s through the eyes of an immigrant. Fresh from Lithuania, Jurgis; his wife, Ona; and their family are forced to scrape for survival after moving to Chicago in hopes of chasing the American Dream.

From the very beginning, they fall upon hard times when the house they purchase is found to be in shabby condition and has hidden fees that the family can't afford. With the financial burden that the family is faced with, even the youngest family members are forced to find jobs in plants and factories to contribute what they can.

Jurgis works in an unheated meat-packing plant and is eventually injured on the job and is forced to stay home and recover, but his employers simply refuse to pay him until he is able to return to work. His father finds a job to help keep the family afloat, but sadly the old man dies from the terrible working conditions. Ona, his wife, continues to work, but when her boss commits a terrible act, it leads to Jurgis attacking him and getting sent to jail.

Eventually, Jurgis loses everything and turns to a life of crime for survival. After another stint in prison, Jurgis realizes that he must join the Socialist Movement in order to feel better about his lot in life. Filled with unfair situations, terrible working conditions, and broken promises, The Jungle is a cry for socialism and the call for reform of the working conditions during Sinclair's lifetime.