The nation's favourite : the true adventures of Radio 1

Five years ago, BBC Radio 1 gained a new controller.

Matthew Bannister said he was going to reinvent the station, the most popular in Europe.

But things didn't go exactly to plan. The station lost millions of listeners. Its most famous DJs left, and their replacements proved to be disasters.

Radio 1's commercial rivals regarded the internal turmoil with glee.

For a while a saviour arrived, in the shape of Chris Evans.

But his behaviour caused further upheavals, and his eventual departure provoked another mass desertion by listeners.

What was to be done? In the middle of this crisis, Radio 1 bravely (or foolishly) allowed the writer Simon Garfield to observe its workings from the inside.

For a year he was allowed unprecedented access to management meetings and to DJs in their studios, to research briefings and playlist conferences.

Everyone interviewed spoke in passionate detail about their struggle to make their station credible and successful once more.

The result is a gripping and often hilarious portrait a much loved national institution as it battles back from the brink of calamity.