Okay, so I kinda need help finding the title of a book. So, it's about a group of kids who work for a pair of dudes (IIRC). They solve a bunch of mysteries and stuff. At the beginning of one book, the generic smart kids picks up a Kris (a weapon used by the Malays), and they have to figure out a mystery about a treasure. There's a tree that looks like it has a face, on an island. There's also a dude named Roary.
