The Secret Letter

There is a killer out there waiting in the shadows for an innocent woman called Sarah. She was handed a letter that she thought was not much of anything until someone started to follow her. She has to travel all over the world to get away from this killer. On her way to getting away from this killer, she discovers clues, bodies, treasure and a secret kept from her all of her life. Why is this killer after her? What does he or she want? Is it the treasure they are after or could this secret she will find out later, be something that could destroy them? Let's see if you can figure out who the killer is and why he, she or they want the letter and Sarah so much.