But the Krell forgot one thing.
3 seconds sound clip from the Forbidden Planet (1956) movie soundboard.
You can hear this line at 01:24:53 in the Blu-ray version of the movie.
Quote context
[...]
- Morbius was too close to the problem.
- The Krell had completed their project.
- The big machine... no instrumentalities... true creation.
- Come on, Doc, let's have it.
- But the Krell forgot one thing.
- Monsters, John. Monsters from the id.
[...]