 The same team reunited for "Planet Earth" (2006), the biggest nature documentary ever made for television and the first BBC wildlife series to be shot in high definition.In 2009, he co-wrote and narrated "Life", a ten-part series focussing on extraordinary animal behaviour, and narrated "Nature's Great Events", which showed how seasonal changes trigger major natural spectacles.In 2011, Fothergill gave Attenborough a more prominent role in "Frozen Planet", a major series on the natural history of the polar regions; Attenborough appeared on screen and authored the final episode, in addition to performing voiceover duties.