For slug lines, I know you're supposed to provide 3 pieces of information only, such as:

INT.  BEDROOM -- DAY

However, I have many scenes that take place in various individuals' rooms.   Is it acceptable to say something like the following:

INT.  MARY'S BEDROOM -- DAY   or
INT.  AL'S LIVING ROOM -- NIGHT    ???

If not, then I can easily say something after the slug line such as:  

"Having invited Jim over the night, Mary awakens with a panic attack in her room;" something like that to indicate specificity.


Thank you.

I'd put full slug line every time. Better to be safe than sorry.

One thing to keep in mind is that you want to use the same slug for the same location each time. So, I would go with MARY'S BEDROOM if it's visited more than once.

The reverse is not necessarily true. The slug FOREST PATH could appear several times but not be the exact same location (for example, the soon-to-be-victim hikers are going along the trail, making some progress while the story jumps elsewhere).

The purpose of slug lines is to denote a physical location. That location then has to be scouted, or a set built for it, or VFX created for it.

You want to be consistent with that location throughout your script. Screenwriting software can spit out a list of all the locations in your script, so if you call a location "AL'S HOME" in one slug and "AL'S HOUSE" in another, it will be treated as two different locations.

Beyond that, you will often have locations with a location. Like in your example, the bedroom and the living room of the same house. You still need a slug line whenever you change locations because it requires a new camera setup for the new location and sometimes it might even be an entirely different filming location (the bedroom of one location and the living room of a different location) pretending to be all the same location within the film.

In those cases, you still want to use the same slug line and add an additional location within it (INT. AL'S HOUSE - BEDROOM - DAY or INT. AL'S HOUSE - LIVING ROOM - NIGHT).

You can even transition from sublocation to sublocation by using a mini-slug:

Quoted Text INT. AL'S HOUSE - BEDROOM - DAY Frustrated, Al tears off the pillowcase and crams it into a ball. He storms out the door, muttering to himself. LIVING ROOM Al thrusts the pillowcase down into the couch as far as he can. He adjusts the cushions and inspects his handiwork. Satisfied, he flops onto the couch and breathes a sigh.

Here, we understand that LIVING ROOM is still within AL'S HOUSE. Usually you would reserve this for a principal location, one you spend the majority of time in. It doesn't help to have LIVING ROOM within Al's House and within Mary's House because that locations list will treat both as the same if they are called the same thing.

Of course, there are no hard rules saying you have to follow this methodology. All that's important is you be clear and consistent with your slug lines, and give each location a unique identifier. A generic location like FOREST PATH would likely all be filmed at one location from multiple angles to make it seem like multiple locations, so that's perfectly fine.

Rene pretty much nailed it

Thank you all!   Really appreciate the insight!