Nature Immunology, Published online: 08 September 2026; doi:10.1038/s41590-026-02650-z Chimeric antigen receptors (CARs) have revolutionized engineered cell therapies for cancer. Impressive anti-tumor effects have now been achieved by fitting CARs onto fused macrophage–neutrophil hybrid syncytial, with a promising outlook for stand-alone and combination therapies.