Note: This episode contains strong language.Today, we’re sharing Episode 2 of “Rabbit Hole,” a New York Times audio series with the tech columnist Kevin Roose. In this episode, we hear from a young man named Caleb who was pulled into a vortex on YouTube: “The truth is down there, and you’ve got to go down and dig for it.” What was he watching on the platform? And why was it so transfixing? If you're tuning in to "Rabbit Hole" for the first time, start with the prologue. You can find more information about the podcast at nytimes.com/rabbithole.