The video sees director Ruben Fleischer and stars including Ryan Gosling and Anthony Mackie discussing their hope to make the movie this generation's "iconic gangster film".
The film centres around 1940s real-life gangster Mickey Cohen (Sean Penn), who was targeted by a special LAPD task force.
Emma Stone, Nick Nolte, Josh Brolin, Giovanni Ribisi and Michael Peña also feature on the cast.
The release of the movie was pushed back from the summer following the cinema shooting in Aurora, Colorado. A scene in which mobsters open fire on an audience in Grauman's Chinese Theatre on Hollywood Boulevard has since been reshot.
Gangster Squad will open on January 11.