“Parasitoids” are defined as different from “parasites” in that they ultimately kill their host, and among the most nefarious of these are those that are able to manipulate the behavior of their host, keeping them alive only until they no longer need them. This unfortunate katydid is in the process of having a horsehair worm (Nematomorpha) vacate its body. Although the katydid is still alive, the worm has slowly devoured most of its internal organs while growing inside to many times the length of its host’s body. Even when fully developed, the worm keeps from killing the insect because it uses it for transport – somehow compelling the katydid to seek out a source of water where the worm can finally complete its life cycle. Yasuní National Park, Ecuador.