Synopsis
Developed by Japanese TV company NHK, the image intensifier (II) system has a camera chip 300 times more powerful than the standard digibeta camera used for most wildlife filming. It took only LED headtorches to light the cave sufficiently to see the 'gloworms'. Previously, they'd been filmed using time-lapse which creates a flashing effect that doesn't actually occur.

Electrolysis of aluminium | Inside the Factory
Cherry travels to Scotland to visit the UK's last remaining factory that produces aluminium via smelting and electrolysis.

The End of God?: A Horizon Guide to Science and Religion
Thomas Dixon delves into the BBC's archive to explore the troubled relationship between religion and science, from the creationists of America to the physicists of the Large Hadron Collider.