Ghostbusters

— There's something very important. I forgot to tell you.
— What?
— Don't cross the streams.
— Why?
— It would be bad.
— I'm fuzzy on the whole good/bad thing. What do you mean, «bad»?
— Imagine all life as you know it stopping instantaneously and every molecule... in your body exploding at the speed of light.
— Total protonic reversal.
— Right, that's bad. Okay.

- There's something very important. I forgot to tell you.
- What?
- Don't cross the streams.
- Why?
- It would be bad.
- I'm fuzzy on the whole good/bad thing. What do you mean, «bad»?
- Imagine all life as you know it stopping instantaneously and every molecule... in your body exploding at the speed of light.
- Total protonic reversal.
- Right, that's bad. Okay.