In a new Nature Microbiology paper, Jan Wohlfarth (ETH Zurich) and colleagues show that Listeria and Enterococcus can evade phage predation by transient conversion to a cell wall-deficient L-form state, which is triggered by endolysins disintegrating the cell wall ‘from without’. Results suggest this represents a population-level persistence mechanism to evade eradication by phage. Read also this discussion of the paper by Thomas Denes (University of Tennessee, Knoxville).