Ariel Manto is writing her PhD thesis and has a facination with a book called 'The End of Mr. Y', which no-one alive has ever read. That's partly becasue everyone who has had anything to do with the book has either died or disappeared.
Ariel finds a copy of this book, quite unexpectedly, in a local bookshop and learns it's secret; the book contains a recipe for a potion which allows you to enter an alternative dimension, 'The Troposphere'. Once in the Troposphere, you can travel around using the thoughts of others.
This is the start point for what turns out to be an adventure through science, religion, self-doubt, self-loathing and ultimately, love.
For those people who have read Popco, The End of Mr Y follows a similar kind of narrative. Thomas appears to have taking a load of subjects she is interested in (homeopathy, religion, quantum physics) and fused them into one glorious whole.
I loved this book. She did lose me a bit when describing the fourth-dimension, quarks, time and matter and all the electron stuff, but it has to be said, Scarlett Thomas on her bad days is better than most other writers on their best days.
Brilliant. If you liked Popco, you'll love it!