Physicists have discovered a surprising new “Island of Inversion” in a place no one expected: among nuclei where the number of protons equals the number of neutrons. For decades, these strange regions—where atomic nuclei abandon their usual orderly structure and become strongly deformed—were thought to exist only in highly neutron-rich isotopes far from stability. But experiments on molybdenum isotopes revealed that molybdenum-84 behaves dramatically differently from its close neighbor molybdenum-86, even though they differ by just two neutrons.