Ant colonies are one of the wonders of nature: complex, organised... and mysterious. This programme reveals the secret, underground world of the ant colony, in a way that's never been seen before. At its heart is a massive, full-scale ant nest, specially designed and built to allow cameras to see its inner workings. The nest is a new home for a million-strong colony of leafcutter ants from Trinidad. For a month, entomologist Dr George McGavin and leafcutter expert Prof Adam Hart capture every aspect of the life of the colony, using time-lapse cameras, microscopes, microphones and radio tracking technology. The programme explores how these tiny insects can achieve such spectacular feats of collective organisation. It also reveals the workings of one of the most complex and mysterious societies in the natural world - and shows the surprising ways in which ants are helping us solve global problems.