It sounds backwards but this video is completely in black and white but it was shot in colour. As in, everything that you see in the video is actually black and white in real life and was captured to express the real colours in the colorless colours. And it works! Black and white 'in colour' pops so much more than it would if you just slapped a black and white filter on it.
One of my biggest pet peeves in art is the lazily-desaturated DSLR video. "Black & White In Colour" is my personal response to treating black and white as an editing afterthought. This short video is the culmination of a year and a half of experimentation with black and white textures. Please note: in some instances, colour is unavoidable -- dark purples, greens, and blues separate out of black dye within a few minutes.