The Shining - Stanley Kubrick

Jack Torrance: Wendy, let me explain something to you. Whenever you come in here and interrupt me, you're breaking my concentration. You're distracting me. And it will then take me time to get back to where I was. You understand?

Wendy Torrance: Yeah.

Jack Torrance: Now, we're going to make a new rule. When you come in here and you hear me typing...

[types]

Jack Torrance: ...or whether you DON'T hear me typing, or whatever the FUCK you hear me doing; when I'm in here, it means that I am working, THAT means don't come in. Now, do you think you can handle that?

Wendy Torrance: Yeah.

Jack Torrance: Good. Now why don't you start right now and get the fuck out of here? Hm?