Gallery: These 40 Serial Killers Who Have Never Been Caught Are What Nightmares Are Made Of

What was that noise outside? Is that the silhouette of someone behind you that you’re seeing in your computer screen? Look, it’s probably a good idea to avoid reading about serial killers that are still at large when it's dark out; especially if you live alone. In the last house on the left. In Amityville, New York. You get the idea. But, if you just can’t help it, if you’re ravenous for info about serial killers that are still at large, then keep on reading. Just, uh, maybe put a knife under your bed?