A new documentary about Diana, Princess Of Wales will aim to tell "the definitive story of the most famous woman in the world" to mark what would have been her 60th birthday.
The one-off ITV film, entitled Diana, will use never-heard-before testimony and rarely seen archive footage, as well as photos and letters from those close to her to trace her journey from nursery assistant to royal family.
It will be produced by 72 Films, whose previous work includes The Rise Of The Murdoch Dynasty, directed by Bafta winner Jemma Chisnall.
David Glover, executive producer for 72 Films, said: "There is something a bit magical about Princess Diana, and despite the difficulties in her personal life she managed to use her connection with people to do huge amounts of good.
"Her 60th birthday feels like the perfect time to re-examine her life and legacy and explore just how she went from a relatively unknown teenager to the most mourned person who ever lived."
Jo Clinton-Davis, controller of factual entertainment for ITV, added: "This year would have been Diana's 60th birthday, and the intention with this landmark documentary is to offer the definitive account of her life, both in front of the cameras and behind the scenes.
"It is a difficult undertaking to shed new light on the most emotional, dramatic and pivotal elements of the life of Diana, when that light still burns brightly.
"But by delving deep into her relationships with friends, colleagues and staff, our aim is to provide a vivid portrayal of the woman who became known as the Queen of Hearts."
The channel will also show a three-part series called Diana's Decades, which will follow her early royal life, her high-profile work for HIV charities, her brushes with Hollywood and music superstars in the 1980s, and her journey to becoming the People's Princess and emblem of a new public emotional candour in the changing face of Britain under New Labour in the 1990s.
Daniela Neumann, of production company Spun Gold TV, said: "Nearly 25 years on from her tragic death, Diana, Princess of Wales continues to lead our news bulletins and conversations not just in Britain but around the world.
"Diana's Decades takes a fresh approach to recounting her life and legacy by looking at how she was shaped by the changing world around her and as a result transformed not just the monarchy but also society more widely as her legacy."