Frantic to change her life, quit drinking, and save the world, Sil and her boyfriend leave their jobs and travel to Phoenix, where they'll await the green light for a new job in Haiti building eco-friendly homes.

Once on the road, one regret clouds Sil's excitement. To push away the shame, Sil continues to drink, but she also buys a new notebook. As she journals, a voice who claims to have lived long ago writes her back, responding to her pleas for help. Sil dubs this voice Cave Woman.

Sil's well-earned skepticism keeps her questioning Cave Woman, who patiently explains the evolution of addiction and helps Sil unwind her past. While Sil holds out hope she can escape her problems by running off to save the world, Cave Woman has other ideas about where this trip is leading.