Long John Silver plays diplomat, delivering the captured Billy Bones to a newly-freed slave community and negotiating with its Julius, to be equal partners in ruling Nassau and defying the British, if they spare Billy's life.
Silver and Julius are unaware, though, of the unfolding Spanish invasion force of a dozen ships and 1,000 soldiers.
Eleanor Guthrie, believing her husband Rogers has sailed south to Port Royal, has left the fort to consummate the treasure-for-safe passage deal she engineered with Capt. Flint. Rogers told his Spanish counterpart she and others would be hiding in the fort and struck a deal with them to leave her unharmed.
The Spanish naval commander tells Rogers after landing and not finding her at the fort, he would be powerless to stop his soldiers from attacking whomever they pleased.
Silver tells Billy, who's being held prisoner by newly-freed slaves, that if he swears to drop his vendetta against Flint, he'll make sure he goes free, but Billy rejects the offer, telling Silver he made his choice to side with Flint. As the Spanish attack, a pirate, with Silver's blessing, unshackles Billy and tells him "good luck."
Capt. Jack Rackham, already incensed by Eleanor and Flint telling him a deal has been made to part with the Urca d'Lima treasure he once held, berates Max, who shows up on the beach trying to find Eleanor and get her to safety. Still, he asks Max to join him in fleeing aboard the Walrus, Capt. Flint's ship.
As the newly-patched pirate-Maroon-freed slave alliance makes a desperate last stand to hold Nassau against the overwhelming Spanish forces, Eleanor and Madi find closure in a safe house, discussing the history that has bound them.
But that house isn't as safe as they think. A Spanish soldier kills Madi, as she tries to defend Eleanor. Then the soldier — after failing to rape a physically resisting Eleanor — kills her. Rogers later discovers her dead body.
Silver learns of Madi's death, but even in his despair tells Flint he doesn't blame him. The Walrus heads south to the Maroon colony, where the Urca cache has been delivered.
Ann rejects Max's offer to take care of her, but Jack listens to Max's advice to sail to Philadelphia and recruit Eleanor's grandfather to finance a plan to avenge her death by killing Rogers.