Critics widely hailed There Will Be Blood as one of the most important American films of the 21st century, praising its ambition, formal control, and thematic depth. Reviewers highlighted Paul Thomas Anderson’s direction for blending an intimate character study with an epic portrait of American capitalism and ambition. The film frequently appeared on year‑end “best of” lists, with many critics singling out its bold pacing, long takes, and willingness to embrace ambiguity rather than tidy moral lessons. Its exploration of greed, religion, and power was often described as both timeless and eerily resonant with contemporary concerns about corporate excess and resource exploitation. Critics praise Daniel Day-Lewis' performance, emphasizing his ability to capture a sense of horror in the slow moral degradation of his character.