Scott Esposito in Literary Hub:
The Missing Books is a living document. As Esposito discovers more missing books (and as circumstances demand changes to this list) Esposito will update The Missing Books and release new editions. Anyone who purchases The Missing Books is entitled to all future versions of it, for free.
The Passenger by Cormac McCarthy (Reputed manuscript-in-progress by Cormac McCarthy.)
McCarthy’s most recent novel, The Road, was published in 2006, ten years prior to the time of this writing; at no other point in McCarthy’s 50-year career has the author let such a span pass without publishing a new novel. He has reportedly filled this time with two major projects, The Passenger being the one about which the most is known. Some light was shed on The Passenger in August 2015 (creating a small media firestorm) when McCarthy appeared at a Lannan Foundation event where he reportedly read excerpts from the book. The Passenger is said to be a very long book set in New Orleans, and there is conjecture that it engages theoretical physics and tropes of science fiction to a large degree. Additionally, there are reports that the book has been continually pushed back and may at one time have had a 2016 release date.
More here.