The 51st State (also known as Formula 51) is a 2001 action comedy film directed by Ronny Yu, written by Stel Pavlou, and starring Samuel L. Jackson, Robert Carlyle, Emily Mortimer, Ricky Tomlinson, Sean Pertwee, Rhys Ifans, Stephen Walters and Meat Loaf. The film follows the story of an American master chemist (Jackson) who heads to Britain to sell his formula for a powerful new drug. All does not go as planned and the chemist soon becomes entangled in a web of deceit.

The film premiered in the United Kingdom on 7 December 2001. It was released internationally under the title Formula 51 in October 2002, where it grossed $14.4 million, just over half of the budget.