A modular shelf system for a bath or shower wall, comprising one or more shelves and a panel, wherein the panel comprises a flange configured to be parallel planar with a bath or shower wall, the panel comprises a cavity configured to removably receive the one or more shelves, the panel cavity is configured to be recessed within the bath or shower wall, the one or more shelves are configured to be removably coupled to the panel cavity, and when the one or more shelves are removably coupled to the panel cavity, they are configured to resist being inadvertently pulled out of the cavity and inadvertently tilted.