Chimeric antigen receptor (CAR) T cells have revolutionized the field of cancer immunotherapy. Genetically redirected killer CD19-CAR T cells have achieved lasting therapeutic effects in patients with B-cell leukemias.1,2 In a brilliant new twist on this system, Ellebrecht et al., as recently reported in Science,3 have conceived of chimeric autoantigen receptor (CAAR) T cells to specifically eliminate autoreactive B cells. Their strategy is reminiscent of that of angler fish. In the dark depths of the sea, the angler fish has developed a clever way to lure its prey by dangling a luminous appendix in front of its powerful mouth.