The best mystery book I have ever read was "The Oblong Crate" by Edgar Allen Poe. It was a really wierd book and I really enjoyed it. It kept you guessing and it had a pretty cool ending.
My short mystery starter is going to be the sentence after this one. "It was a cool morning with a summer breeze when all of a sudden, aliens came down to Earth and put viruses in our ears while we were sleeping(duh duh duh),then they left.