Revealing mistake: When Ando has a vision of Ryuji waking up on the operating table and tilting his head up to look at his hollowed-out body, you can see where the fake prosthetic body and neck are blended with the actor's face, and even see a little bit of the actor's real neck beneath his head.
Revealing mistake: When Ando makes the first incision into Ryuji's body during the autopsy, it's very clear that the skin is a fake prosthetic made of some sort of soft, spongy material. The knife glides into it unrealistically easily, almost like a hot knife through softened butter.
