The evolution of cancers to resist existing therapeutic strategies has constantly led researchers to design next-generation therapeutics. Research on nanomedicine holds significant potential in developing newer cancer therapeutics. Nanozymes bearing the properties of enzymes can be promising anticancer agents due to their tunable enzyme-like properties. In one such approach, a biocompatible cobalt-single-atom nanozyme (Co-SAs@NC) bearing catalase and oxidase-like activities that function in cascade at the tumor microenvironment has been reported recently. The current highlight discusses this investigation to unveil Co-SAs@NC's mechanism in tumor cell apoptosis through in vivo studies.