This is a modular, Phase II, multicenter, single-arm, open-label study to evaluate the efficacy and safety of surovatamig (AZD0486) monotherapy administered as an intravenous (IV) infusion in participants with relapsed or refractory B-NHL. The purpose of this study is to determine the efficacy and safety of surovatamig (AZD0486) administered at the RP2D in adults 18 years of age or older with relapsed or refractory B-NHL.