Miranda Sawyer with the third episode of her series about the world of podcasts, rounding up some of the best from around the globe. This week: podcast pioneers, the agenda-setting podcasters who have broken new ground in the genre.

Miranda hears from the creators of Welcome to Night Vale, who talk about their perhaps unlikely surrealist pod hit.

The programme also features Wendy Zukerman's Australian-based science podcast Science Vs, recently bought up by Gimlet Media, an increasingly powerful new media player in the burgeoning podcasting market.

Ben Hammersley, internet technologist and journalist, and the man who invented the word "podcast" guests.

Producer: Jim FrankResearcher: Chris Pearson.