James Holmes opened fire at a movie theater in Aurora, Colorado, killing 12 and injuring 70 others.

James Eagan Holmes is an American mass murderer responsible for the 2012 Aurora theater shooting in which he killed 12 people and injured 70 others at a Century 16 movie theater on July 20, 2012. He had no known criminal background before the shooting occurred. Before the shooting, Holmes booby-trapped his apartment with explosives, which were defused one day later by a bomb squad.

On July 20, 2012, a mass shooting occurred inside a Century 16 movie theater in Aurora, Colorado, United States, during a midnight screening of the film The Dark Knight Rises. Dressed in tactical clothing, 24-year-old James Eagan Holmes set off tear gas grenades and shot into the audience with multiple firearms. Twelve people, as well as an unborn baby, were killed and 70 others were injured, 58 of them due to gunfire.

Aurora is a home rule city located in Arapahoe, Adams, and Douglas counties, Colorado, United States. The city's population was 386,261 at the 2020 United States census with 336,035 living in Arapahoe County, 47,720 in Adams County, and 2,506 in Douglas County. Aurora is the third-most-populous city in the State of Colorado and the 51st-most-populous city in the United States. Aurora is a principal city of the Denver–Aurora–Centennial, CO Metropolitan Statistical Area and the Denver-Aurora, CO Combined Statistical Area, and a major city of the Front Range Urban Corridor.