Quentin Blake's secrets of drawing

Roald Dahl's estate has revealed several characters that were written in drafts of his book Charlie and the Chocolate Factory, but did not feature in the final edit.

Dahl wrote five edits of his story, four of which survive. The latest revelations describe unknown characters that include up to 10 golden ticket holders. In the final book there are only five.

The illustrator Sir Quentin Blake was responsible for bringing the characters to life with his drawings.

He was first introduced to Roald Dahl in 1975 and collaborated with him on several books including James and the Giant Peach and The Witches.

Mr Blake spoke to BBC News about the Charlie and the Chocolate Factory characters that did not make it to the final book and how he went about bringing the novel to life.