This week we delve into the Dark Web, a hidden arm of the Internet where Google doesn't dare to search and where drugs, guns and hitmen are offered up for sale. We explore how the World Wide Web works, and ask whether it can remain unregulated, free and open as it is now? Plus, in the news this week, the worm found lurking in a patient's brain, how scientists have grown pain nerves in a Petri dish, and what do dogs hear when we speak to them? Like this podcast? Please help us by supporting the Naked Scientists