Star Wars Cast Didn't Know About 'I Am Your Father' Scene Until Movie Was Out

Mark Hamill said it was "agony" to keep that plot twist a secret from his costars for over a year

Things Only True Fans Noticed About Star Wars' Iconic 'I Am Your Father' Scene

Darth Vader - Wikipedia

Luke Skywalker - Wikipedia

Father' twist in 'Star Wars' was so secretive, cast didn't know until movie came out

Darth Vader's Original Voice Was More Hilarious Than Terrifying, #DarthVader's Original Voice Was More Hilarious Than Terrifying, By /Film

I Am Your Father: Cass Sunstein on George Lucas, Anakin Skywalker, and Star Wars's Dad Complex - The Atlantic

Star Wars V: The Empire Strikes Back (Limited Edition) [DVD] : Mark Hamill, Harrison Ford, Carrie Fisher, Billy Dee Williams, Anthony Daniels, David Prowse, Peter Mayhew, Kenny Baker, Frank Oz, Alec

The Original Empire Strikes Back Script Shows Darth Vader Wasn't Supposed to Be Luke's Father

How Mark Hamill and George Lucas Kept the Darth Vader Father Twist in Empire Strikes Back a Secret

Star Wars: Revenge of the Sith : Ewan McGregor, Natalie Portman, Hayden Christensen, Ian McDiarmid, Frank Oz, Jimmy Smits, Peter Mayhew, Ahmed Best, Oliver Ford Davies, Temuera Morrison, Anthony Daniels, Silas