Recently, there has been a massive trend of Chinese international PhD graduates returning to China's research-intensive universities that are undergoing systemic reforms and aspire to flourish in the global higher education field. Taking into account this changing academic environment and field-specific mobility patterns, the study examines the case of 14 early career science, technology, engineering, and mathematics (STEM) returnees employed in one of such institutions. Informed by a temporal perspective on agency, we present their academic reintegration experiences negotiated on national/local and institutional levels and unfolding in multiple realms of their post-return lives. Findings derive three prominent themes concerning their encounter with Chinese work culture encompassing entrenched and emerging features, embeddedness into local academic communities of exchange, and navigation of transformative possibilities within the institutional framework of career excellence. Importantly, the study underscores that structures internal to the university can profoundly shape the way returnees leverage their cosmopolitan assets and the direction they take in envisioning their transnationally viable career paths.