For Thai students, English-speaking skills have been among the most problematic. This study aims to compare the English-speaking skills of English for Specific Purposes (ESP) students before and after employing movie circles, and to investigate their attitudes toward employing movie circles. The participants consisted of 30 ESP students studying a dual program in social development and education at a public university in Thailand. They were also classified as pre-service social studies teachers. A mixed-methods study was performed utilizing the one-group pre-test-post-test design. Both qualitative and quantitative methods were employed. The instruments were movie circle lesson plans, pre- and post-English-speaking tests, an attitude questionnaire, and semi-structured interview questions. The results revealed significant improvement in the ESP students’ English-speaking skills, as well as positive attitudes toward using movie circles to improve English-speaking skills. The findings suggest that movie circles, or peer-led discussion activities, can be integrated into ESP classrooms with the specific goal of improving English-speaking skills.