The western corn rootworm continues to be on the rise in Europe. Why attempts to biologically target this crop pest by applying entomopathogenic nematodes have failed, can now be explained by the amazing defense strategy of this insect. In their new study, scientists from the University of Bern, Switzerland, and the Max Planck Institute for Chemical Ecology in Jena, Germany, show that the rootworm larvae are able to sequester plant defense compounds from maize roots in a non-toxic form and can activate the toxins whenever they need them to protect themselves against their own enemies. (eLife, November 2017, DOI: 10.7554/eLife.29307.001)