Otis is finally found dead after a while. The reason it took so long to find him is that he was held underwater by weeds. Brodie was afraid that Otis was still alive and Otis was trying to make him go insane.
Hannah and Brodie go on to a bat watching trip/date. They go during sunset so they can watch the bats leave the cave. Hannah likes conducting studies and watching the bats as her dad did many years ago in Florida. (This is why some people call her the Batgirl.) Hannah confesses to Brodie that she was the one who planted the towels and left the note.
In the end, Brodie confesses to his parents about the accident. They are extremely shocked and disappointed. Brodie is especially shocked by his mom's reaction. She said "SON!" which she never said before.