I have to confess, I am curious about tomorrow's essential person working on a movie set.

We've had "grip", and "gaffer", could it be "best boy"?*

Every movie set has a best boy
Who the gaffer will quickly deploy
To light the stage
Or discreetly engage
The siren as her boy toy.

P.S. Even if "best boy" isn't the word tomorrow, it gives me another shot at "gaffer" today. :)

Or, could it be the "cinematographer", I wonder?

The "cinematographer" is certainly the deserving subject of an AWAD -- and also of an ALAD:

A movie’s cinematographer
Is the story’s videobiographer.
He creates each scene
To fill the screen
To become a cinemaOscarographer.

* Yep. The AWAD for Day 3 is best boy:

best boy (best boi) noun
The first assistant to the gaffer (head electrician) of a film crew. [Apparently borrowed from the sailing terminology.] per Anu