The Secret Genius of Modern Life

Hannah Fry discovers the hidden WWII radar technology that heats up baked beans, learns the legend of the melted candy bar in an engineer's pocket that kick-started a kitchen revolution, and puts her life on the line to demonstrate why microwaves zap food but not people!

Headphones: these marvels of miniaturisation are worn by over 30 million people in the UK. Hannah Fry visits legendary headphone honchos Bose to find out how today's teeny earbud tech works and meets the human testers with ‘golden ears'.

She discovers how helicopters in the Korean War helped put the ‘shhh' into noise-cancelling, why it took a muted Mormon church service to get headphones onto people's heads, and how an opera singer's electric shock therapy led to the invention of the speaker.

Hannah goes behind the scenes to look at the technology behind the lift, entering a 246m high lift shaft to test everything from the brakes to her own fear of heights.

Along the way, she finds out how rickety 19th-century coal mines made lifts safer, gets to grips with a piece of medieval siege technology still used in lifts today, and discovers how an 1850s PR stunt changed the modern skyline forever.