Karen: If we had found you a bit later you'd've been dead, but we didn't save you out of kindness you can belive that, you and your friends found something didn't you, and then one of them betrayed you. Don't try to hide it.
Keisuke Hirata: Yes, we found what we were looking for, the opal.
Karen: An opal?
Keisuke Hirata: That's right, one that's this big, my brother found during the war, he hid it in that cave himself, and so by rights it's ours.