When marine biologist Roger Hanlon captured the first scene in this video he started screaming. (If you need to see it again, here's the raw footage.) Hanlon, senior scientist at the Marine Biological Laboratory in Woods Hole, studies camouflage in cephalopods--squid, cuttlefish and octopus. They are masters of optical illusion. These are some of Hanlon's top video picks of sea creatures going in and out of hiding.