I have to obey him or I'll be left all alone. And then... And then I won't be able to figure out what this is all about. I won't be able to know his master plan.

15 seconds sound clip from the Donnie Darko movie soundboard.

You can hear this line at 01:41:14 in the Blu-ray version of the movie.

Quote context

[...]

- You did it again?

- I flooded my school and I burned down that pervert's house.

- I only have a few days left before they catch me.

- Did Frank tell you to do these things?

- I have to obey him. He saved my life.

- I have to obey him or I'll be left all alone. And then... And then I won't be able to figure out what this is all about. I won't be able to know his master plan.

- Do you mean, God's master plan? Do you now believe in God?

- I have the power to build a time machine.

- How is that possible? How is time travel possible? Donnie?

- Time's up, Frank said.

[...]