adding a dirty noisy effect

[mcbeth]

I’ve working on a toon effect for the longest while and have reached a stage where I would like to add a noisy like dirty affect similar to below, but I am unsure of how to go about setting it up, from looking at the image the noise affect bleeds into and out of heavily shadowed area any advice would be greatly appreciated

this is where I’m at so far just need to get the noise affect going and figuring out some shadowing issues

[FloridaJo]

You could bring a ‘grunge’ texture into the node system and then use a mix node to either multiply or darken or some other blend mode with your render layer node image output to cause your output to have that look.