Fade prerecorded video into Video Device In feed

Hello,
This question might be very simple, but I cannot find any answers online.
I am trying to have a prerecorded video fade into a Live camera feed from Video Device In.

I have a video that when it finnishes playing through I want the opacity to slowly fade so that it transitions into the live feed from a camera. I have included a screenshot of my very basic setup

Any help with this would be greatly appreciated