Sometime in the mid-2010s, a neuroscientist, a chemist, a lab tech, an IT geek, and a financier created NME 110. This drug was supposed to cure the neurological deterioration caused by schizophrenia. Instead, an overdose of the drug causes sustained, realistic hallucinations of the divine. When its creators overdosed and one of them was murdered, the group shattered. One became a recluse, another was sent to prison, and a third (our narrator), went to an institution to deal with her addiction and hallucination.
Lyda Rose, a neuroscientist, returns to the world after nearly a decade in a mental hospital after another inmate kills herself. Lyda believes that it was withdrawal from NME 110 that drove the girl to despair because it made her feel like the divine was leaving her. Though her doctor is very reluctant, Lyda gets her walking papers and a drug monitoring chip in her arm. The trail of NME 110 leads her to a strangely peaceful prison inmate turned preacher who is giving the drug away for free, to give people a little peace as long as their supply is not interrupted. Lyda is not the only one on the drug's trail. The Millies, a group of Afghani women who used micro loans to become marijuana dealers, are right behind her because they want to get rid of their competition. There is also a mysterious cowboy, under orders to follow Lyda and stop the distribution of NME 110.
As if this isn't enough, Lyda Rose also needs to make peace with her past. Gregory slowly reveals what happened the night the drug's creators overdosed and what happened to Lyda's wife, Mikala. Mikala's death haunts Lyda because she feels responsible. Lyda feels responsible for so much that even her new conscience, the angel Dr. Gloria, tells her to let things go. Her guilt hampers her relationship with Ollie, another mental patient whose abuse of a drug that enhances pattern recognition drove her deep into paranoia.
As a thriller, this book is great. The mystery is skillfully played, with plenty of twists and turns. It's incredibly well written. Gregory's first three books are great, but this one is incredible. As science fiction, Afterparty is original and well-designed. Psychopharmacology is endlessly fascinating to me. One chemical or protein or enzyme can mean the difference between schizophrenia, Parkinson's disease, and neuronormalcy. In Lyda's world, recreational and pharmaceutical drugs are available everywhere now that dealers can "print" them with chemjets. The brain is surprisingly delicate, but capable of so many amazing things, like creating a personality.
What makes this book great is the question of what NME 110 does. Is Lyda's angel just an exceptionally powerful hallucination? There are hints that might make you think otherwise. Is NME 110 opening a channel to the divine, as so many users believe? Perhaps. Is there such a thing as free will? Maybe not. Gregory never gives you a definitive answer and I adore this. I'm going to be thinking about all the topics Afterparty raises for a while.