Not terrible overall and the general idea isn't over-used, even during the holiday season in question (as so many are in the media)...

A few suggestions have come to mind for future development, since you've asked...

First, I might suggest the whole of characters and scenery gets a darker general shade, a few highlights can also be used to create the starker, more "noire-esque" atmosphere that would likely benefit the character.

Second, a few more sound effects will help "sell" your shots and actions better, even some voice-over laughters, chatters, or an occasional gasp, etc would add quite a bit. Even a "bad" audio is better than nothing.

Finally, and maybe this is just a question of style, but I might suggest a few heavier chords into the music score... Maybe listen to some older school gothic or death metal to find the right additions. This score does get the idea across, but it sounds a little more light and whimsical than seems to fit the imagery.

Now, take your time, and I can't stress that enough in these developments (or any others) just try going over things with one at a time, and see which gives the proverbial "best bang for your buck" as you move on.
And honestly, I think the "rough" look to the drawing style already adds a sort of noire effect to it, so only mess with that at your own peril.

I dig the black and white style, although it seemed a bit too gray for my tastes. Perhaps next time you can have just a bit more contrast, give it a bit of a black and white noire look?
And I'm not sure if you're aim for this character is too make him a bit silly but that's what he came across as. I can see this character doing some pretty sinister things.
Hopefully you elaborate on this character further and create more animations of him!
Keep working, keep improving!

The drawings have a rough look to them and are not completely smoothed edged.

I personally prefer the rough look over the completely clean smooth brush strokes.

The graphics can be farther enhanced by utilizing hand painted backgrounds for a more interesting look.

I like how you created a back and white animation.

This movie has some great drawings and uses some very creative character designs.

Who are these characters?

I would like to learn about the personalities of your creations.

You've caught my attention but the show can be improved upon by making it longer.

I look forward to seeing more movies from you.

-Mightydein