Information has major consequences for democracy and society. It is important to understand what factors favor its diffusion. The impact of the content of a message on its likelihood of going viral is poorly understood. Some studies say originality is important for a message not to be overlooked. Others give more relevance to paratextual elements—network centrality, timing, human cognitive limits. Here we propose that originality and centrality interact in a nontrivial way, which might explain why originality by itself is not a good predictor of success. We collected data from Reddit on users sharing hyperlinks. We estimated the originality of each post title and the centrality of the website hosting the shared link. We show that the interaction effect exists: if users share content from a central website, originality no longer increases the odds of receiving at least one upvote. The same is not true for the odds of becoming one of the top 10% scoring posts. We show that originality is concentrated in the domain network: domains in the core of the network produce more original content. Our results imply that research on online information virality needs to take into account the nontrivial interaction between originality and prominence.