Duplicate original layer.
Use threshold to simplify image on one layer.
Select simplified image.
Hide altered layer and unhide original.
Select/Inverse to cut away background.
step 2 of 7
I used a brick pattern that I had created previously at 100% opacity on the Pattern Overlay menu.
step 3 of 7
Added a layer behind the cat and selected a brick colored gradient.
step 4 of 7
Added the brick Pattern Overlay to the gradient layer and moved the cat to line up the brick lines.
step 5 of 7
Reduced the opacity of Pattern Overlay on the cat so that the cat's features are visible again.
step 6 of 7
Changed blending modes on the cat layer to Pin Light to create the ghostly look.
step 7 of 7
Merged the two original layers.
Reduced the size of the resulting image by 10%.
Added a layer behind the cat/wall layer and filled with black for a nice border.