I think the concept is good and could be powerful but it stumbles in a few areas.
Format wise, you use too many parentheticals. Don't direct the actors from inside the script. That's the director's role, not the writer's. Your dialogue and scene descriptions should provide context for the actor and director to realize the scene. Use a parenthetical very sparingly. Especially with the beats or pauses. It is very annoying to me as a reader, actor and director. My honest advise is to strip them all out. A parenthetical is only used when the dialogue suggests opposite the intention. For example
Code:
SARAH
(sarcastically)
Oh, I love that hat!
Without the parenthetical, Sarah may be making an actual compliment. The (sarcastic) helps the actress know that is not the case.
If you're directing this, you correct the actor to get the delivery you want. Trust the actor.
Structurally I think the pacing dragged. Some of the dialogue was too one-the-nose or conversational. As a result, the ending was predictable.
Development wise, the characters were all rather flat and stereotypical. I didn't care or relate to any of them. As a result, I had to force myself to continue reading. If this were a contest script, I'd have passed.
I think it is a good start but needs to be reworked to remedy the issues mentioned above.