A versatile breast cancer-targeting nanocomposite therapeutic combining docetaxel (DXL), polyvinyl alcohol (PVA) network for controlled release, and silica-protected magnetic iron oxide nanoparticles (Fe O NPs) for targeted delivery and gold nanoparticles (AuNPs) for plasmonic photothermal therapy (PPTT) is presented in this work. First, the designed nanocomposite is magnetically directed for cancer-targeted therapy confirmed by computerized tomography (CT) scans. Second, 10% DXL by mass is loaded into PVA, a pH and temperature responsive gel, for controlled release. Third, PPTT is confirmed with Au/Fe O /PVA-10%DXL using a prototype circulation system and then for tumor treatment in vivo; Au/Fe O /PVA-10%DXL is conveniently directed and the entrapped DXL is selectively released (≈96%) via the interaction of green and near-infrared (NIR) light with the localized surface plasmon resonance of AuNPs. A 75% cell death is reported from in vitro studies with DXL doses as low as 20 µg mL of Au/Fe O /PVA-10%DXL, and a 70% tumor growth inhibition is demonstrated by in vivo experiments with the biosafety studies confirming minimal side effects to other organs. Overall, the developed Au/Fe O /PVA-10%DXL has a strong potential to simultaneously enhance CT imaging contrast together with the targeted delivery of DXL.