Scholars have long seen radicalisation as a predominantly group based phenomenon, occurring largely through ‘real world,’ in person interaction. By contrast, the internet is seen as playing only a limited ‘facilitating’ role in radicalising people to violence. However, a series of attacks by far right extremists over the past decade has demonstrated that this perspective is less accurate than it once was. Almost none of these terrorists were members of extremist groups and had only engaged with other extremists on the internet. In this article, we examine the relative importance of face-to-face group interaction and physically isolated internet-based radicalization in driving individuals towards extremist violence. We do so through a detailed case study of Action Zealandia, New Zealand’s leading ideological white nationalist group. The study is based on eighteen months of infiltration of the group by one of the authors from 2019 to 2021. When interacting online, members often adopt highly extremist personas, in some cases threatening mass violence. By contrast, face to face interaction and group membership pushed the group away from extremist violence. This was due to several factors: police pressure and a lack of opportunity for the movement to grow, and the often uninspiring nature of offline interaction.