He betrayed and murdered your father.
4 seconds sound clip from the Star Wars: Episode IV - A New Hope (1977) movie soundboard.
You can hear this line at 00:34:25 in the Blu-ray version of the movie.
Quote context
[...]
- It's your father's lightsaber.
- He betrayed and murdered your father.
- Now the Jedi are all but extinct.
- Vader was seduced by the dark side of the Force.
(R2-D2 Beep Blip Blip Beep) (2)
- Now let's see if we can't figure out what you are, my little friend, and where you come from.
[...]