Secret passage effect??

Say, for example, I was filming a wall, and I wanted to make the wall slide up to reveal a secret passageway or something. How would I go about doing this?

Here’s how I think I would do this if asked:

  1. Film the wall.
  2. Either (a) film with the wall gone using the same camera movement, or if this isn’t an option (b) proceed to step 3 part B.
  3. (a) Model a replica of the wall in Blender, match move the footage, and composite. The first part of the shot would be just the wall, which would then blend with the CG wall. The animated CG wall section would then reveal the final part of the shot, being the footage without the wall. (b) Same as part A, except you model and render everything behind the wall as well.