Award-winning film-maker Don Letts explores the work of photojournalist Kent Gavin, who for more than 40 years worked as the Royal Photographer for the Daily Mirror. The series offers a rare glimpse beyond the constraints of the Palace walls, as Gavin opens up an incredible vault of never-before-seen photographs that capture the royal family's most intimate moments. He is one of only two photographers asked by The Prince and Princess of Wales to photograph Prince William's christening. Gavin is interviewed in the programme, as is Piers Morgan, Sir Michael Parkinson, Anne Robinson and many more.