Human scientists are still trying to figure out how to turn cloaking devices into a reality, but the pint-sized Hawaiian bobtail squid long ago learned how to channel its inner Klingon. See its natural cloaking device in action inside.
Thankfully, this particular squid is only about 30 millimeters long. That's a very good thing, because if any giant squid had its knack for cloaking and camouflage, I'm pretty sure it would have already conquered the world. Here's the video explaining the absurd array of tricks the squid has up its tentacles to avoid being seen: