21 Bridges is a 2019 American action-thriller film directed by Brian Kirk and written by Adam Mervis and Matthew Michael Carnahan, based on a story by Mervis. The film stars Chadwick Boseman as an NYPD Detective who shuts down the 21 river crossings of Manhattan to find two suspected cop killers, portrayed by Stephan James and Taylor Kitsch. Sienna Miller, Keith David and J. K. Simmons appear in supporting roles. The film was produced by brothers Joe and Anthony Russo, Mike Larocca, Robert Simonds, Gigi Pritzker, Boseman (in his only producing credit) and Logan Coles. It was also Boseman's final theatrical film before his death in August 2020. His last two films, Da 5 Bloods and Ma Rainey's Black Bottom, were released on Netflix.

The project was announced as 17 Bridges in July 2018. Principal photography began on September 24, 2018 in New York City, primarily Brooklyn, and also took place in Philadelphia, Pennsylvania. Several members of the cast joined the film in October 2018, including James and David.

21 Bridges was theatrically released in the United States on November 22, 2019, by STXfilms. It received mixed reviews from critics and grossed $49 million worldwide on a $33 million production budget.