Considering the rising tide of international student return mobility, the UK needs to pay attention to the long-term circulation and development of international student returnees. This study analyses the mobility, variations and pathways of the transnational in-between identity of Chinese student returnees from the UK, an under-researched group in the changing dynamics of international student mobility. This longitudinal study uses original data from 48 semi-structured interviews to show how student returnees' identities change over time in transnational sociocultural contexts. This study develops a spider chart comprising multiple manifestations of transnational selves to account for returnees' intermediary and heterogeneous states of transnational in-between identities. Based on the empirical evidence, the study finds that transnational in-between identity is characterised by a 'self-in-between mobility', seeking compromises and connections between the polar extremes of essentialist and non-essentialist approaches to identity. In such an identification process, the changing dynamics of agency play a pivotal role in (re)shaping multiple identity pathways as variegated temporal outcomes of mobility. The findings not only advance the theoretical and methodological constructs of identity, but also have implications for relevant concerns in international education.