This study explores the acting coaching methodology during the rehearsal process of the play "A Very Cruel Disappearance." The play is a contemporary reinterpretation of Sophocles' "Oedipus Rex" within the framework of the lower class, with a modern setting and a spatial background based in Korea. Despite the shift in temporal and spatial contexts, there is a significant reliance on the actor's body and text, mirroring elements found in Greek tragedy. While grounded in naturalistic expression, the work places a strong emphasis on corporeality and materiality. Drawing inspiration from Aristotle's "Poetics," the study seeks a return to fundamental elements, pursuing realism while focusing on the expansion of illusion, particularly emphasizing the audience's aesthetic experience. The researcher employed Michel Chekhov's 'Psychological Gesture' and Eugenio Barba's 'Body-Mind' in acting coaching, aiming to awaken corporeality during the rehearsal process. Efforts were made to guide actors in embodying 'action' through their physical activity, leading to emergent moments in performance. Departing from the conventional use of psychological gestures as a training tool for actors to feel appropriate emotions during the rehearsal process, this study sought to actively utilize it for expressive purposes, showcasing the psychological state of the characters to the audience. Additionally, building on the Body-Mind approach, the study sought a methodology where the nuanced movements of the characters could reflect reasoned perceptions. This approach aimed to visualize thought processes and break down the boundaries between the actor and the character. Through this physical training process, the study attempted to dissolve the boundaries between the actor and the character, leading to performative spontaneity. This research serves as an exploration of this process, and it is hoped that it will contribute to the further expansion and development of physical training methods in the future.