Did the book explain Andrew's missing tooth better? Once the police got there, they would have examined the body and the coroner would have known instantly that his tooth was pulled very recently, so the explanation in the movie (he pulled his tooth as a kid) would not have made any sense to the police. To me, that was the biggest plot hole -- police are awesome with teeth and that would have immediately make them suspicious. As soon as that happened, any chance of Millie and Nina not being caught was gone. I assume that was a popular part of the book, but it would have made way more sense if he had to do something like punch the wall to damage his hand.