I would've given this at least a 4 or 4.5, but there's a good number of flaws I've noticed.
First, the good -- The colors you used for this animation is well-selected; the blacks work well to contrast the high-intensity of the colors. And the minimalistic design on the characters is a nice choice for this look.
Okay, now the bad -- During the scene when the cops and the ambulance arrived at that woman's house, all your animation, and all the action happening is way too close to the bottom of the screen. There's so much negative space in that scene, I almost missed on what's happening.
Not to judge on the choice of music, but the fast pace of the music doesn't really match well to the slow-timing of the animation. (Okay, maybe I'm not the best guy interpreting the lyrics of the song) For example, when the guy's knocking on the door three times, he just walked back in a normal pace. That doesn't tell me well enough that he's worried of what's happening.
Again (if you'd rather keep that timing of the animation), it goes upon the staging, composition issues. May if you have some close-up shots of the characters, maybe that will enhance the mood of the song.
Not saying this video's bad, (I like it and all) but a lot of things can be improved.