A pre-lap is when the dialogue (or any sound) from the next scene starts before we cut away from the previous scene. They are a common and useful transition.
Pre-laps are often inserted in editing, but they can also be written into scripts.
Dialogue pre-laps are indicated with the parenthetical “(PRE-LAP)” next to the character’s name — not below it — and in all caps:
EVAN (PRE-LAP)
Oh man, that looks good.
INT. A LOTTA GELATO – DAY
Evan watches as Adam eats.
EVAN (CONT’D)
Stupid fluoride.
If the sound is something other than dialogue, it can be set off like this:
ADAM
How bad can it be?
PRE-LAP: A drill BUZZES.
INT. THE OFFICE OF DR. BOLSKI, DDS – DAY
Adam watches as Evan writhes in pain under the dentist’s tool.
* [Pre-lap](http://johnaugust.com/2007/pre-lap “Pre-lap”)
* [Talking over a black screen](http://johnaugust.com/2011/talking-over-a-black-screen “Talking over a black screen”)
* [Introducing off screen characters](http://johnaugust.com/2005/introducing-off-screen-characters “Introducing off screen characters”)