Soy protein-based biomaterials have been widely studied in functional polymer blends and composites. The diverse polymer-protein interactions, resulting from complex protein structures, and their significant roles in tuning structures and functionalities were studied in polyethylene oxide (PEO) /soy protein isolate (SPI) films. The cover image taken by Zhuoyuan Zheng and his colleagues presents the fibrillation of PEO spherulites caused by unique PEO-SPI interactions. The findings in this study will help understand and utilize the interactions between synthetic polymers and natural proteins to develop such functional materials. DOI: 10.1002/app.46561.