Oil! is a novel written by Upton Sinclair and published in 1927. The novel tells the story of an oil tycoon named J. Arnold Ross, who builds his wealth by exploiting the resources and labor of the American Southwest.

The novel is a critique of the oil industry and the capitalist system that allows individuals like Ross to become incredibly wealthy at the expense of workers and the environment. Sinclair portrays Ross as a ruthless businessman who will stop at nothing to maintain his power and control over the oil industry. He also highlights the exploitation of workers, particularly Mexican migrant laborers, who are subjected to dangerous working conditions and low pay.

Upton Sinclair (1878-1968) was an American author, journalist, and political activist. He is best known for his muckraking novel, The Jungle (1906), which exposed the unsanitary and dangerous conditions in the meatpacking industry in Chicago.