This week, I was in Cheltenham for another amazing science festival. It was a fantastic chance to share a stage again with Emeritus Professor Kevin Warwick, whose company I have enjoyed many times. I also met the fantastic Mark Miodownik. Together, we unravelled the world of superheroes and explored how closer we have come to making them a reality. I talked about the promise and peril of technology, the number of ways in which we are already superhuman, and how the idea of what it is to be a superhero has changed over time. Here's what I did.