We kick things off with one of the longest-running experiments in the world. As Joshua Foer explains, the Pitch Drop Experiment is so slow, you can watch it for hours (check out the live cam) and not detect the slightest movement. But that doesn't mean nothing's happening. Professor John Mainstone tells us about his desperate attempts to catch the flashes of action hiding inside this decades-long experiment.

Then, Carl Zimmer joins us for a little recalibration. It’s hard to imagine anything faster than a thought that just pops into your head. But that kind of thinking is actually wrong-headed. In reality, thoughts are achingly, even disturbingly slow. Seth Horowitz, author of The Universal Sense: How Hearing Shapes the Mind, helps us discover our fastest possible thought, and fight our way back into the now.