Stimuli‐responsive metal–organic polyhedra (srMOPs) functionalized with azobenzene showed UV‐irradiation‐induced isomerization from the insoluble trans‐srMOP to the soluble cis‐srMOP, whereas irradiation with blue light reversed this process. Guest molecules were trapped and released upon cis‐to‐trans and trans‐to‐cis isomerization of the srMOPs, respectively. This study provides a new direction in the ever‐diversifying field of MOPs, while laying the groundwork for a new class of optically responsive materials. Lock in the guests, later set them free: Stimuli‐responsive metal–organic polyhedra (srMOPs) functionalized with azobenzene showed UV‐light‐induced isomerization from insoluble srMOPs substituted with trans‐azobenzene to soluble srMOPs with cis‐azobenzene units; irradiation with blue light reversed this process (see picture). Guest molecules were trapped upon cis‐to‐trans and released upon trans‐to‐cis isomerization of the azobenzene units.