This paper analyses the ‘gangster’ subculture of boys aged 15–18 years in a secure care unit for young offenders in Denmark. By drawing on a specific case from a 2-month field study, the paper demonstrates how three boys teach a new boy to become a ‘real gangster’. This learning process not only reveals central elements in what constitutes the ‘gangster subculture’ in the secure care unit but also shows constituents of the subculture in which the boys live their everyday lives outside secure care. Learning to be a ‘gangster’ involves both short- and long-term learning processes. The short-term process is closely linked to learning the specific ‘gangster style’. The long-term learning is closely connected to experiences of growing up in areas of ‘advanced marginality’ and life on the streets celebrating values of respect, loyalty and crime, all subcultural values formed by the intersections of class, ethnicity and gender. The paper suggests that understanding the ‘gangster’ subculture calls for taking its cultural expressions seriously in terms of the intersection of class, ethnicity and gender formed in everyday practices.