Couple of years ago, an angry neighbor starts banging on my door.

Yeah, yeah. Stop all that banging, I heard you the first time, banging on the door.

Cognitive recalibration. I hit you really hard on the head.

Please enjoy my ecosystem of love. Never tap on the glass!

What are you doing in my bedroom? Yeah, well, I knocked on the front door, but you didn't hear it.

Was he the one who used your head to open a nut? No.

A good way to check it's ready, give it a little tap and listen out for a hollow sound.

Didn't want to. I thought you found another investigator. I felt rejected. Well, we were broke.

Oh, that's awful! I know. It's also why I never open a door without knocking three times.

Anybody can bang, bang, bang. But to make music, you have to listen to each other and keep in time.

Why don't we just knock on the door and talk to him? I tried. Yeah, the guy's a jerk.

Oh. This is so exciting. Oh God. Come and knock on my door. We'll be waiting for you.

Penny! Penny! Penny! Sheldon, honey, I've told you, it's a small apartment. You only have to knock one time.

You mean the man with the motorcycle helmet, the man who came to my door, who wanted to come in and have a beer and wait for you?

And so far they've come up with: Hey, why don't you drill holes in the roof of your Rover and hit it as hard as you can with a rock.