Given the rise in cultural diversity in workplaces due to increased globalization and hyperconnectivity, organizations worldwide are seeking effective ways to attract and retain multicultural talent. This research probes the interaction between an employee’s cultural intelligence (CQ) and a supervisor’s CQ, investigating how this interaction impacts work engagement and the intention to stay within multicultural work groups. Drawing on work engagement literature and leader-member exchange (LMX) theory, we conducted two empirical studies. Study 1 (170 matched data) reveals that employee’s CQ positively influences work engagement, with this relationship moderated by the supervisor’s CQ. Study 2 (161 matched data) validates these findings while also demonstrating how work engagement influences employee’s intention to stay. Taken collectively, our research advances theory and practice by elucidating the synergistic value of fostering both employees’ and supervisors’ CQ—i.e., the “double CQ”—for enhancing engagement and retention in multicultural work groups.