Jellyfish behaving badly -- At the mercy of jellyfish -- Some astonishing ecological impacts -- Jellyfish completely out of control -- Jellyfish, planetary doom, and other trivia -- Jellyfish: the basics -- Overview of ecosystem perturbations -- Overfishing: a powerful agent of ecosystem change -- Eutrophication almost always leads to jellyfish -- Pollution destabilizes ecosystems -- Biopollution: the twelfth plague -- Climate change changes everything -- The weeds shall inherit the earth -- The allee effect, trophic cascades, and shifting baselines -- The jellyfish double whammy -- High-energy and low-energy ecosystems -- The oceans are dying to tell us something -- Ocean acidification: the "new" problem -- The rise of slime.