Sir Terry Pratchett documentary planned by BBC

Sir Terry wrote more than 70 books over the course of his career

A "humorous documentary" about the late fantasy author Sir Terry Pratchett has been commissioned by BBC Two.

Terry Pratchett: Back in Black will tell his story in his own words, with comedian Paul Kaye voicing the writer.

"Terry wanted to... write the story of his life as a writer but he never got around to it," said Mark Bell, head of commissioning for BBC Arts.

The creator of the Discworld series died in 2015, eight years after being diagnosed with Alzheimer's disease.

The film, to air on BBC Two later this year, will feature contributions from authors Neil Gaiman and Val McDermid.

Rob Wilkins, the writer's long-serving assistant, said they had been working on the documentary during "the last few months of Terry's life".

Wilkins said the film would follow the "trilogy" of TV documentaries Sir Terry made between 2009 and 2013.

In a statement, the BBC said the programme would show the author was "still having the last laugh".