Cut out object but keep shadows

Hi,
I am doing a character in Blender and would like to use it as a PNG assets with in a video software.

I am using a plan to have a shadow.
So I need a render in with the character is cut out with the shadow.

My problem is that I did not manage to have a cut out of the character and keep the shadow without having the plane on the render. I am using cycle.

Thanks