ABSTRACT In this article, I aim to demonstrate how a contemporary novelist can write about extremism in the social media age and in the process engage with the literary consciousness of the past. Although several novelists have written about extremism in recent years – notably Kamila Shamsie in Home Fire (2017), Guy Gunaratne in In Our Mad and Furious City (2018) and John Wray in Godsend (2019) – few efforts have yet been made to show how it relates to the experience of life online. I argue that for a novelist wanting to explore extremism today the precursor it would be most valuable to revisit is Fyodor Dostoevsky. He perceived how in mid-nineteenth-century Russia the new mass medium of the newspaper was transforming consciousness and heightening radical sentiment, and explored this in Crime and Punishment (1866) and Demons (1871). Through a sustained engagement with these works, I interrogate the opportunities offered by entering into dialogue with him and consider how his most important narrative technique, polyphony, can be reimagined in the social media age.