Snack or stylis? 🌭 #SecretGenius #iPlayer Subscribe and 🔔 to the BBC 👉 https://bit.ly/BBCYouTubeSub Watch the BBC first on iPlayer 👉 https://bbc.in/iPlayer-Home Hannah Fry uncovers the secrets behind the miraculous technologies of the modern world, revealing the mind-blowing stories behind their invention. All our TV channels and S4C are available to watch live through BBC iPlayer, although some programmes may not be available to stream online due to rights. If you would like to read more on what types of programmes are available to watch live, check the 'Are all programmes that are broadcast available on BBC iPlayer?' FAQ 👉 https://bbc.in/2m8ks6v.