A modest girl is pressured by her overbearing mother into partaking in a dangerous aging experiment that could benefit humanity and please her mother but ruin the girl?s life as she knows it. Now, the girl must learn to cope and escape this newfound nightmare.

>>>As far as the doctors are aware the child was completely on board and that it was her idea.

I suggest you do some research on contemporary medical ethics.? Only an immoral physician would suggest or consent to experimenting on a minor with a risky procedure that radically alters human maturation .? And immoral physicians, willing to cut corners, violate their Socratic oath do exist. So...

Just saying the mom needs an equally immoral and vanglorious co-conspirator.

fwiw

It seems to me that your story hinges on creating a world in Act 1 where it is credible to believe that children can be sacrificed on the altar of medical science "for the greater good" .? That they can offered up against their will, without their voluntary consent as "lab rats".? A violation of every norm in contemporary medical ethics.? And a re-incarnation of the medical experiments the Nazis performed.

That would, indeed, be a horror story.

What is the putative benefit humanity might gain at the daughter's expense?? In general terms, what is the "aging experiment" , to? have the child prematurely age in order to, well,.what?? Why is the ideal "human/rat" a young person?

I agree that this is an interesting situation. I can assume what the protagonist?s goal is, but it is better for you to include it in your logline to avoid confusion. And I agree with the previous comment, what does the mother gain from using her daughter for an experiment? Is she doing this to help humanity as a whole? Or is she doing it for more selfish reasons?

And what's in it for the mother?? Why would she allow her daughter to be used as a human guinea pig?? ?Not to mention the violation of just about every medical ethic.? It seems to me the proper genre is not thriller but horror.

This is an interesting situation, but what is the lead character's goal, and what is standing in the way of that goal?