Yes, I know you have your doubts, but grey is a colour too and in the right combination, it can actually become an accent colour in itself, not just a neutral.
I like a lot of black and white and reds, navies and now grey. And I really like pushing myself to create outfits within the confines of themes.
Usually, when doing capsules (this is my 4th this year), the difficulty is making pieces work together, especially if you have prints or loads of colours. For this one, I had the opposite problem. How can I make things look interesting with just three colours to work with and all three neutrals to boot. I did get a bit of help from my trusty red accessories (scarf and earrings), but I also made things harder by only using two pairs of shoes, black and silver.
I am looking forward to showing you what I ended up with and of course, to hear what you think.