The script reveals how producers managed to keep the film’s famous twist – the revelation that Vader was Luke Skywalker’s father – secret even from its stars.
Prowse died in November at the age of 85. While he provided the character’s physical performance, Vader was voiced by James Earl Jones.
In the film’s climactic moment, Vader tells Luke (played by Mark Hamill): “I am your father”.
However, Prowse’s script has Vader say: “Luke, we will be the most powerful in the galaxy. You will have everything you could ever want... do not resist... it is our destiny.”
The script is being auctioned by East Bristol Auctions. The organisation’s auctioneer, Andy Stowe, explained the misdirect in the script to CNN.
“The only people that knew I think were about three or four members of the cast,” he said.
The script, which is marked with the word “Vader” at the top of every page, is expected to be sold for between £2,500 and £4,000.
Other Star Wars memorabilia items are also being featured in the auction, which will take place on 4 May, known internationally as Star Wars Day.
Access unlimited streaming of movies and TV shows with Amazon Prime VideoSign up now for a 30-day free trialSign up
Join our new commenting forum
Join thought-provoking conversations, follow other Independent readers and see their replies