The expansion of simulated 'free-to-play' gambling-themed activities on social media sites such as Facebook is a topic of growing research interest, with some conjecture that these activities may enable, or otherwise be associated with, gambling and problem gambling. This paper describes findings from an in-depth qualitative study which aimed to explore the interrelationships between social casino games, gambling, and problem gambling. Social casino games are typically promoted via social media sites (e.g., Facebook) and involve structurally realistic simulated forms of gambling (e.g., poker, slot machines). Ten adult users of social casino games were asked to describe: (1) their history of experiences with these activities, (2) their exposure to promotions relating to social casino games, and, (3) the perceived influence of these activities on their gambling behaviour. Respondents reported frequent exposure to promotions for social casino games and that being connected to a social network of players was a significant factor in determining their engagement in these activities. However, involvement in social casino games did not appear to affect the likelihood of gambling or the risk of problem gambling. Some problem gamblers did report, however, that these games could sometimes trigger a desire to engage in gambling. Interestingly, social casino games were commonly perceived as a safe activity that may act as a substitution for gambling. Further empirical research should investigate this possibility in more detail.