Why wont this work!

yep its saturday night and im here trying to get something unbelievably simple to workk… but it wont…

have a photo on 1 layer and then have a line drawing of a woman which i want to give the effect of it being drawn on the layer above… so i thought id use a mask to get the effect of the woman being drawn… however this wont work for some reason…

any ideas… i am a newbie so you can start from scratch and dumb ity down for me!!!