maya created character with real movie background

hello to all
i badly need information, if it is possible with maya to solve my problem:
we have created a 3d character in maya who moves, because we wanted to create an animation movie. the plan was to put the character over an reel filmed movie, as a background, quicktime or avi.
is it possible to put the real movie behind the animation and render it? that it looks somehow good?
how we can realize this?
thanks a lot