Running on Karma (traditional Chinese: 大隻佬; simplified Chinese: 大只佬/大块头有大智慧; Literal Title: Big Guy/Big Guy Has Big Wisdom), also known as An Intelligent Muscle Man, is a 2003 Hong Kong action thriller film produced and directed by Johnnie To and Wai Ka-fai.

Principal photography began from March to July 2003, though filming was interrupted in April due to the SARS pandemic.

Running on Karma was a critical and commercial success, grossing HK$26,339,848 at the Hong Kong box office, making it the third-highest-grossing film of the year in the territory, and received 13 nominations at the 23rd Hong Kong Film Awards, winning Best Film, Best Screenplay and Best Actor for Lau, who wins the award for the second time after being awarded for his performance in Running Out of Time in 2000.

Big then became a bodybuilder and worked in a strip bar when he ran into Lee Fung-yee (Cecilia Cheung).

Big (after realizing that Lee was kind-hearted), decided to help her in the investigation of a homicide, but also swore to leave her after they solved the case.

Big successfully helped the police to arrest the murderer and saved Lee's life in the process as well.

Hilary Hongjin He, a doctoral student at the University of Western Sydney, wrote that the version of the film released in mainland China required "substantial" editing by mainland authorities to the point that it "fundamentally degraded the philosophical, thought-provoking movie to a senseless commercial film selling stars and special effects make-up".