Lung cancers driven by mutant forms of EGFR invariably develop resistance to kinase inhibitors, and this often entails emergence of new mutations. Establishment of lung cancer cells resistant to a second-line EGFR inhibitor called dacomitinib uncovered a previously unknown intermediate step of the process leading to resistance acquisition. The interim step involves acquired features characteristic to epithelial-mesenchymal transition, is nonmutational, and can still be reversed by host factors. The cover image shows spheroids of PC9 cells probed for E-cadherin (green), vimentin (red), and DAPI (blue). For details, see article by Haga and colleagues on page 3862.