"there will be blood" is partially based on upton sinclair's novel 'oil!'. paul has said that in writing the script, the story deviated from the book a great deal and evolved into its own thing. the production was delayed for more than a year to clear up legal and financial issues before being shot in summer 2006. the shoot lasted about three months, most of which took place in marfa, texas, with reshoots occuring in the first half of 2007.

throughout the production, a cryptic photo blog has been maintained, known as 'little boston news'. the blog is named after the location which most of the events of the film take place in (little boston).

robert elwsit returned to shoot the film, and dylan tichenor is returning as paul's editor along with newcomer tatiana s. riegel. jonny greenwood scored the film.