In a big city lived two sisters who looked nothing alike. One had dark brown eyes as dark as night the other one had bright blue eyes as bright as day. Their names were Norah and Alexandra. The two loved to solve mysteries together, but apart from that, they had to manage their disagreements. 

The sisters had two best friends helping them solve mysteries, but they were the main detectives. Norah and Alexandra lived in San Francisco but solved mysteries all over the world. Their first mystery was in Guanajuato. They were just ending their trip in Mexico and wanted to finish it by staying in Guanajuato for two weeks.

They were enjoying their stay at a hotel packed with excitement when they accidentally overheard a conversation at the table next to them in the restaurant. One person remarked, "The guy in room 907 has it. His great-grandfather passed it down to him. It’s made of solid 24-karat gold."

Norah's eyes lit up as she said, "I bet they’re talking about the legendary golden pocket knife!" 

"Room 907 is a luxury suite, and I heard a prince is visiting Guanajuato while we’re here. Do you think—just maybe—he’s staying in our hotel?" I dunno, said Alexandra, there are lots of hotels, why would he pick ours out of lots? Well, I don't know why. Let's go to the room and do a little research. Later in the afternoon, Norah said Look what I found, Alex, the prince's old house is right across the street from the hotel. I wonder what he could be doing in the hotel across the street?

They decided to go ask him in his hotel room. They got in the elevator and went all the way up to the 9th floor, and walked to room 907, and when they knocked, the door creaked open, and in the hall, there lay the prince. They checked all his pockets, but there was nothing but a note that said, "  To the person who reads this, I have taken the golden pocket knife, do not seek me or you will regret it, signed, C.H. Who could C.H. possibly be? Asked Alexandra.

Let me look it up, I'll tell you if I find anything. Ok? Fine, I'll be over in my bedroom watching TV.

A little later, Alexandra said Hey, look at this. The prince was poisoned, but he survived thanks to us finding him. It's all over the news. Oh my, I am so glad he is still alive. Yes, and we should go visit him in the hospital, it is so good that we speak fluent Spanish.  

When they got there, they went to the princes room and he said thank you so much for saving me I really appreciate it but I can't tell you any thing about the golden pocket knife. Oh that's okay we understand said Norah.As they walked away she said with a smug grin "we'll do the research ourself". Alexandra just smiled. when they got back to the room they decided to spy on the prince and squeeze some information on why he's here and what he has to do with the golden pocket knife and C.H .