The focus of this thesis is research of interaction which takes place between players and computer games. Specifically on ethical and moral aspects of such interaction in which the players are required to make moral decisions that in any way affect the progression of the story, shaping of the virtual world, or have any other effect on the in-game narration. The goal of this text is to describe context in which such moral decisions are made and factors that influence them. The theoretical part of this thesis has the form of a summary of relevant game studies topics, which influence the moral decision making issue. Research was conducted on a group of ten respondents, who played The Walking Dead game and who shared their experiences by answering questions concerning moral decision making. The gathered data was thereafter analysed using a grounded theory method, which allowed me to identify and contextualize the researched phenomena. The main output of this text is the grounded theory itself and the answers provided by its application in context with research questions.