Specific project help - Masking?

Hi Guys,

I'm trying to get a specific shot made on FCP. Subject is lay down in front of TV. I want to put something different on the TV. So I just used the distort function and sized up some B-roll footage so it looked like there's something else on the TV.

Problem is that when subject walks in front of the TV, he walks BEHIND the distorted layer and so the effect is ruined.

Is there any way to make an effect so that when he walks in front of the TV, he remains in front of the layer?

Hope this makes sense.

Thanks to anyone that can help!

Phil x

Stack a copy of the clip on top of your effects layer. Mask out the TV screen section. Invert the mask.