So there was an audio drama of ANH put out in 1981 by NPR. It's pretty good, I've always thought. Expanded on the movie's scenes in various interesting ways. I'm posting now because it actually
shows the scene where Vader tortures Leia for information. He uses the Force and mind games and... it's really awful and intense.
Also, it's one of the very few early-Star-Wars-things that could be used to sell the idea that Lucas had the whole story planned from the start. He claims that, but there's not much evidence, considering.
Personally I don't think much about planned/not planned, but... man, that scene is a lot harsher in light of the rest of the films. Drawing on Mustafar much, Vader? Plus, this is probably the only time he's ever spoken to Leia gently. Definitely the only time he's talked to her as her father, at least until TaB.