Dead at 15

The twelve Lambert sisters were born in order of month, and then named accordingly. On each of their fifteenth birthdays respectively, the first eleven died.

No proper investigation was conducted regarding these deaths. Conclusions were drawn based on circumstantial evidence and no 'serial killer' was charged.

However the youngest daughter, December, has her suspicions. She's going to find the killer. But with just a month to live, December is racing against the clock.
It's a do or die situation. The murderer will be put behind bars, or she'll end up another body in the morgue.