Skull and Bones by John Drake

John Drake set himself the task of writing the backstory of Treasure Island, answering such questions as "who was Captain Flint?" and "Where did the treasure come from and why is it buried on Treasure Island?" This was spread over three books: Flint and Silver, Pieces of Eight, and Skull and Bones.

Flint and Silver introduces us to the characters. By the end, Long John Silver is marooned on the island along with a crew. In Pieces of Eight, Silver's crew fortifies the island for Flint's inevitable return. By the end of the book, Silver is in possession of some of the treasure, the ship the Walrus, and his beloved wife Selena. Flint is in custody of the Royal Navy.

Skull and Bones picks up from there. The book has many twists as Flint, Silver, and Selena take separate journeys that all lead to London then to Annapolis and Savannah. It is the weakest of the three with no strong plot. It is more like one thing after another. It also lacks any exciting battles. There is a battle at the end but the lead characters are more spectators that participants.

Of the three books, Pieces of Eight (the middle one) is the strongest. While it has many twists and turns, it also builds to the inevitable confrontation on the Island. It is possible to read this one separately from the others.

All three books are well-researched and written in a style that sounds both old-timey and nautical. They are eminently readable. I recommend all three.