This show had people gripped of a Sunday evening on the BBC1 last year, but if you missed it, you can watch it from the start tonight on RTE One to see what all the fuss was about. Sir David Attenborough narrates this remarkable documentary series that was the BBC's first ever show to be shot in the Ultra High Definition format. In tonight's opening episode, there is footage of wildlife that inhabit remote islands, revealing the advantages and disadvantages of the creatures' habitat. There's also three-toed sloths (yes sloths - could there be a more adorable animal?) in the Caribbean, Marine iguanas in the Galapagos Islands, as well as penguins on the Antarctic island of Zavodovski.