I picked this illustration by Arthur Rackham for our classic episode on mystery boxes as Pandora's Box stands as the most mythically potent mystery box of all time.
Perhaps you remember the story? The Greek God gave Pandora, Earth's first woman, a mysterious box and ordered her not to open it. But of course her curiosity won out, and all the evils of the world escaped when she lifted the lid. It's much like another famous myth that involves a primordial do-not-touch request from creator to the created.
Arthur Rackham (1867 - 1939) is a legend of the illustration world. You'll find a nice overview of the man and his work right here.