The best mystery I have ever read was Running Out of Time by Magaret Peterson Haddix. I really enjoyed the suspendas that was used to express the story. What made it "the best" was that the author didn't use so many words to write the story, in other words she didn't make the story mushy. 

    What would make a great mystery would be of you started out, "It was dark and cold and wolves were howling all around, Hadley stood in the darkness with her dead cell phone and her jacket. When finally she decided she would try to get home a hand grabbed her and through a blanket on her and all she could her was a faint beeping noise. Suddenly, the blanet was removed and Hadley found herslelf were she never would have imagined herself before..........

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