This paper examines the relationship between Saudi Arabia's domestic and foreign policies under the leadership of Crown Prince Mohammed bin Salman (MBS), divided into three phases. The first phase focused on establishing MBS's legitimacy and consolidating power within the country, while the second phase aimed to gain international credibility. In the third phase, the focus was on consolidating power and formulating a regional strategic policy. The paper is grounded in various theoretical frameworks from international relations and foreign policy analysis, including Foreign Policy Analysis (FPA) and Neoclassical Realism. It argues that shaping MBS's foreign policy is closely tied to addressing the challenges arising from these phases. The research question "How has Crown Prince Mohammed bin Salman's leadership influenced the interplay between Saudi Arabia's domestic and foreign policies?" is answered by highlighting that the interplay between Saudi Arabia's domestic and foreign policy has shifted significantly under Crown Prince Mohammed bin Salman's leadership, resulting in a more assertive and revisionist foreign policy. The paper provides valuable insights into the complex interplay between domestic and foreign policies in Saudi Arabia and the country's challenges in achieving its ambitious goals. It concludes by emphasising the implications of the findings for future research on Saudi Arabia's foreign policy, stressing the urgent need for further exploration of this crucial topic and its broader implications for the region and beyond.