Everybody has to start somewhere. Shakespeare acted in shitty plays he could write in a coma. Pablo Picasso finger painted on the walls of the box his parents kept him in. Mozart wrote music by stomping on his mother's uterine walls. John Woo directed Hard Boiled.
Tequila (Chow) has a problem: too many bullets in his gun. With his bullets, he teams up with an undercover cop (Leung) to take down a group of mobbed up gun runners. They shoot all the things and all the things blow up.
Some movies pride themselves on intricate plots. Others base themselves around a character, an actor's performance. Yet still others focus on cinematography, really getting into the setting and the movement of the camera to achieve beauty in motion. Hard Boiled based itself around high octane violence and fight scenes so crazy people would have to see the movie to understand when their breathless friend began saying "dude there's this movie where these guys kung fu fight but it's mostly shooting like in Lethal Weapon but with so many guns dude you don't even know like this one part with birds and holy shit this other part with a baby it's sick as hell."
You just have to watch it. If you like action, this is the most 90s action movie an action movie could be.