Bitcoin is the world's leading virtual currency, but unlike real money, it is not backed by a government or properly regulated. Bitcoin is exchanged and held digitally by users - which is attractive to criminals selling drugs, pornography and arms. But now Bitcoin is moving into the mainstream and being openly marketed as an investment opportunity. The film investigates what Bitcoin is and what it means, going inside a Bitcoin mine in Iceland - where currency is made - and spending time with the Bitcoin millionaires of Silicon Valley.
The programme also hears from others who have been scammed out of their life savings and investors who think the cryptocurrency is an enormous scam and that the writing is on the wall. Around the world, authorities are sounding the alarm that Bitcoin is too risky - is it too late, or too crazy, to try to become a Bitcoin millionaire?

The digital era gives rise to unprecedented opportunity to exploit, and be exploited. Troves of child pornography are available at the click of a mouse. Who are these children - and who profits from their abuse? While facilitating the darker side of our impulses, technology is also being touted as a cure to rehabilitate predators. In this episode meet the children who are forced to perform sex acts on camera; people who use the same technology to protect kids and nab the perpetrators; plus, a pedophile who reveals the roots of his addiction.

The Internet enables us to connect with people, images and information in ways that were unimaginable 30 years ago. But with every click we are re-wiring the physical structure of our brains. Are we evolving or actively de-evolving down a dopamine-laced click-hole? In this episode meet a 17-year-old boy struggling with an addiction to online pornography; autistic technologists in Silicon Valley who are turning their genetic variation to an advantage; plus, Nootropics, a class of cognition-enhancing supplements that claims to rewire the brain.