- You promised to destroy it.
- When I've carried out my research.

5 seconds sound clip from the The Curse of Frankenstein movie soundboard.

You can hear this line at 00:51:17.386 in the Blu-ray version of the movie.

Quote context

[...]

- Don't you see? I've succeeded!

- Succeeded? Yes, nearly succeeded in getting yourself killed.

- This is my creation.

- Yes, a criminal lunatic. It tried to kill you.

- That's the brain. When you attacked me, it was damaged. That makes it your fault. Your fault that it is not what I intended it to be.

- I can repair the brain.

- It's what I've done that counts. I've created a being.

- You promised to destroy it.

- When I've carried out my research.

- Don't you see you've created a monster?

- That doesn't matter.

- I shall operate on the brain tomorrow. It shouldn't take long.

- Very well, Victor. Goodbye.

- He's gone!

- He's what?

- I've searched the house. Heaven knows where he's got to. It's true, we must get out and find him!

[...]