This paper offers an ethnographic case study of Tomasz, a Polish construction worker, and his professional trajectory as well as daily work life on Norwegian construction sites. The study is based on observations, interviews, and recordings of Tomasz's daily workplace activities and interactions. The Norwegian construction industry is characterized by socioeconomic stratification between permanently employed 'local' and temporarily leased 'migrant' workers. Moreover, due to a high degree of migrant workers in the industry, Norwegian construction sites are often "de facto" multilingual workplaces. This condition entails that multilingual communication and workers with the 'right' language repertoires become valuable. Their value, however, can be volatile and easily appropriated and redefined, as the case of Tomasz will demonstrate. On the one hand, Tomasz, as a worker with the 'right' language repertoire, gains agency and social recognition as being indispensable. Yet, on the other hand, this linguistic valuation also enables continued differentiation and distinction between 'migrant' and 'local' workers. This study contributes to understanding workers' investments in language learning, the conditions of these investments, and how their trajectories make these investments feasible to the workers but also to the companies that hire and lease them.