During the Fourth Drop, you'll enter the Shrine of Dolls (the shrine building you investigated around during the Second Drop). At one point, you'll enter an area called the Flooded Sanctum. It'll be a flooded room with sets of stairs on the west, south, and east sides. At this point, go ahead and load your Type-14 film. (The Type-07 may be strong enough, but I used the Type-14 and I only had one Output upgrade on the camera at this point.)
If you take the east exit from the Flooded Sanctum, you'll be in a room (called Behind Storeroom) that has a shelf of dolls on one side and a lone, kimono-wearing doll right in front of you. After a few seconds, the doll will start to move so whip up the Camera and blast it. You should be able to take it out in one shot.
If you miss this, the creepy little dolls will show up again (I got this achievement while on the west side of the Sanctum in the aptly-named Hallway of Dolls), and of course you can replay the Drop if you totally biffed it.