This master thesis deals with the different technologies that the actor encounters in the process of working in two different media – one of the theater and one of the film. In the work, I will analyse the processes that precede the finalization of an artistic work in both media: from the first meeting with the text/script to performing in front of the audience. In the written part of the diploma exam, I investigate what potential difficulties the actor must be ready to respond to in order for his/her performance to be organic, authorial and autochthonous in the two very different artistic media mentioned above. In this paper, I mostly refer to the theoretical reflections of Susan Sontag, I also used the works of Stella Adler and Lee Strasberg, but also a number of different scientific, academic and essayistic works that I came across on the Internet during my research. I want to point out that the available literature on the mentioned topic in the Croatian theater and film discourse is surprisingly scarce, and it seemed to me that the very translation of these important scientific works from English to Croatian deserves a bigger space in this work. I will also refer to the analysis of acting performance in two media of the same tittle: Tko pjeva zlo ne misli, but also to my own experience of studying at the Academy of Dramatic Art at the University of Zagreb. I will support the claims I am making with comments from my exams and my professional works, which I have reviewed and analysed for writing this thesis. I will analyse certain work processes that influenced my performance in the medium of film and theatre.