An establishing shot establishes the setting of a scene. When we
see a shot of the sun setting behind the exterior of a building,
and then we cut to the inside of that building where our scene
takes place, we have seen an establishing shot. Establishing
shots can be written into your screenplay, but they do not
necessarily have to be marked as establishing shots. EXT.
VELJOHNSON HOUSE – NIGHT Reggie’s room is perched silently above
a glistening pool. INT. REGGIE’S ROOM – CONTINUOUS The FBI
agents stealthily dig through his closet, careful to leave no
trace of their presence. When dialogue is spoken over an
establishing shot (or the previous scene, for that matter), and
it leads into the scene, this is called a “pre-lap,” and should
be indicated as such.