Senescent “zombie” cells are linked to aging and multiple diseases, but spotting them in living tissue has been notoriously difficult. Researchers at Mayo Clinic have now taken an inventive leap by using aptamers—tiny, shape-shifting DNA molecules—to selectively tag these elusive cells. The project began as an offbeat conversation between two graduate students and quickly evolved into a collaborative, cross-lab effort that uncovered aptamers capable of binding to unique surface proteins on senescent cells.