Okay, here it is. In the movie, near the end, Charlie's left thumb is blown off with a gun by Dickie. Remember? Good. When Irene falls into the river, Charlie jumps in after her. When he finally catches up to her and is trying to get her head above water, he suddenly has his thumb back, good as new. It just might be my mistake, but I'm pretty sure that he couldn't have stuck his thumb back on and torn it off again later. Am I right?