The aim of this dissertation is to examine the use of creative metaphors in British political discourse on Brexit, using the cognitive theory of conceptual metaphor and Musolff’s (2016) theory of metaphor scenarios. Analysing metaphors from different perspectives, conceptual domain, metaphor scenarios and the context of use, the dissertation investigates how creative metaphors emerge in British political discourse on Brexit and what rhetorical power these metaphors exhibit. Apart from studying the effects of two cognitive mechanisms based on conceptual domains, i.e. source-related and target-induced creativity, the special attention is given to contextual factors that motivate the emergence of metaphorical creativity. The first part of the dissertation presents the theoretical background, which includes the historical overview of figurative language studies, the basic tenets of CTMM, as well as the overview of studies dealing with metaphorical creativity and political discourse. In the second part of the dissertation, two case studies investigating metaphorical creativity in British political discourse are presented, one dealing with the JOURNEY metaphors and the other with the MARRIAGE/DIVORCE metaphors. The focus of these case studies is to reveal the impact of cognitive mechanisms on the emergence of metaphorical creativity, especially the motivation coming from the contextual factors, the role of metaphor scenarios in producing creative metaphors, and the rhetorical force of creative metaphors. The dissertation shows that metaphorical creativity in political discourse emerges from three cognitive mechanisms, i.e. source-related creativity, target-induced creativity and context-induced creativity, that metaphor scenarios play a crucial role in providing additional and rich conceptual material, used for the creative extension of mappings between the source and target domains, and that the use of creative metaphors in political discourse is necessarily associated with achieving particular rhetorical goals.