Parasites are the most common form of cellular life on our planet and can be defined as organisms that live in or on us, taking from us without giving anything back. Everything from mammals, insects to plants can be infected by parasites- so parasites are incredibly successful. They can hide from our body’s defences and may even change the behaviour of some of the animals they infect. They are also important as not only can they cause terrible diseases but they can be critical elements of food webs and contribute to biodiversity. Find out how parasites are so successful and how new methods of visualisation are helping us unlock even more parasite secrets.