A previously-unheard original vocal which David Bowie recorded for Lazarus, his last release before his death, will be broadcast in a new BBC film on the star's final five years.
David Bowie: The Last Five Years, will feature rare and unseen archive footage and air on BBC Two in January next year, marking what would have been the singer's 70th birthday.
Produced and directed by Francis Whately, it is his follow-up to the acclaimed David Bowie: Five Years, which was broadcast in 2013.
The BBC has released a clip from the film, featuring the vocals and Bowie's longtime producer, Tony Visconti, talking about the recording.
"He would stand in front of the mic and, for the four or five minutes he was singing, he would pour his heart out and I could see through the window that he was really feeling it," the producer said.
"The audio picked up his breathing. It wasn't that he was out of breath. He was like hyper-ventilating in a way, like getting his energy up to sing this. A man on top of his game. It's brilliant. Absolutely brilliant. And the saddest lyrics to hear them now."
David Bowie: The Last Five Years will focus on albums The Next Day and Blackstar, which was released just two days before his death, and the musical Lazarus, which moves to London from Broadway this autumn.
It will also feature "unprecedented access" to Bowie's closest friends.
The documentary's director said he had come to a different view of Bowie while making the new film.
"I always hoped that I would make another film about Bowie as we were only able to scratch the surface in the first film, but I just didn't expect it to be this soon," he said.
"However, looking at Bowie's extraordinary creativity during the last five years of his life has allowed me to re-examine his life's work and move beyond the simplistic view that his career was simply predicated on change - Bowie the chameleon... 'ch ch ch changes' etc.
"Instead, I would like to show how the changes were often superficial, but the core themes in his work were entirely consistent - alienation, mortality and fame."
The documentary is part of a raft of programmes to air in what will be a year on from the veteran musician's death.
BBC4 will broadcast Bowie At The BBC, a compilation of archive footage from his first appearance at the BBC in 1964 through to his death in 2016.
Radio 2 will broadcast a documentary, Life On Mars, presented by Martin Kemp, examining the legacy of the song of the same name.
Radio 6 Music will be asking listeners to vote for their favourite Bowie album and holding a Listening Party for the No 1 choice, and Marc Riley will present a show in tribute to the singer.
BBC2 and BBC4 channel executive Adam Barker said: "BBC Two is thrilled to have commissioned this unique documentary chronicling the most recent achievements of one of the most significant figures in the history of music."