below, the image is completely done in blues, but the more desaturated, the color appears more red when next to the rest of the more saturated blues! It's pretty fantastic.
I'd also like to note, that it was fun not using any layer effects or even any layers with opacity changes! I used a gradient on the background, and I did a levels adjustment at the end because my monitor causes me to print too dark when I go to print things. other than that it was our digital paint and no trickery.
above: This was my original attempt with a gamut mask. As you can see, I originally had a completely different direction in mine. I hadn't gotten far before I got frustrated and wanted to try something else.
above: This was a little bit of value lay-in before I realized I needed to reach out to understand what I wanted to accomplish. I didn't want it to be just blue, but wasn't sure how to introduce more color in to it so the image was color-cohesive.