Watch on SFlix. Ever heard of the Thorium molten salt reactor? That's hardly surprising, as for 70 years, it has been inexplicably kept under wraps by the nuclear industry, despite the fact it could revolutionise energy production. It offers the promise of nuclear energy without waste and without danger. The "green atom": fact or fiction? Research that was dropped without explanation in 1973, has now become a topic of lively discussion...