Need help adjusting a color mask

[madeliner16275940]

Hi all -- new to illustrator so I have a question regarding color masks (and masks in general). What I'm looking to have is a difference mask that only shows up over the layers and not on the white background. For example: 

I have a rectangle with a blending property of "difference." What I want is for just this mask to just be visible over the two people, warping to their shape and potentially a few others. I've tried looking up tutorials but am at a loss, so any information would be greatly appreciated. 

Clicking the "make mask" button just makes the color disappear. I'm not quite sure how to use that option. 

[Ton Frederiks]

Does grouping and Isolate Blending work?

[Mike_Gondek]

1. Select black shape of people
2. Copy to clipboard
3. Select the glow form TV
4. Edit >> Paste in Front
5. Shift click on glow to add to selection (you will have 2 objects the glow, and the black popeople shape on top
6. Object >> Clipping Mask >> Make

The shape you use for the mask, must be on top of the artwork you wish to clip

[madeliner16275940]

This isn't working, unfortunately. Or maybe I'm understanding wrong. If I put the shape of the people on top of the pink color, then that color correction layer is no longer working

The people are originally blue, and I like how the magenta corrects their color into a smooth black. If I put the blue people on top, though, then nothing happens.

I am also terrible at using illustrator, so it could just be me

Turning it as a clip group does this though (im not even attempting to add the TV glow yet)

[madeliner16275940 · Accepted solution]

I think the easiest thing for me to do will just to be to erase the rectangle carefully and make it inline with the shape of the people