Visit the Museum in Dawnstar

During your travels around Skyrim you will be confronted by a messenger who gives you a message for your eyes only, the note says to travel to dawnstar and help a dark elf clean his museum. When you get to the museum there is a strange man in there who says "he asked me to clean the museum, well he asked the wrong person" upon completeing listening to him you turn to your left and there is the body of the owner stuffed in a desplay case.