Determined to cash in on Lowe's debt to her, Kate enlists the physician's help with her husband, Balfour. After a brief examination - and some testy questions from the inquisitive Balfour, who thinks Lowe seems familiar - Lowe decides what Balfour requires is not medical assistance. To Kate's surprise, he recommends unconditional love.
Meanwhile, renowned pirate Captain Sam Valentine arrives (albeit blindfolded) at the request of Blackbeard, who offers him the just-finished chronometer built by Balfour using the decrypted blueprints. The catch for Valentine is twofold: first he must sell it to William Jagger, the man obsessed with finding Blackbeard, and then he must acquire two so-called "hellburners." Once Jagger takes the chronometer back to England, Blackbeard will no longer appear alive... and thus will be free to operate with impunity. But Valentine refuses to participate in the scheme since accepting the offer would end piracy altogether. Not so good for business, in his opinion.
Despite Valentine's refusal, Blackbeard allows his old friend to remain on the island. Valentine repays his apparent kindness by recounting an embarrassing story about Blackbeard and even insulting him face to face. Blackbeard manages to leave the confrontation without bloodshed... until that night, when two of Valentine's pirates corner him at his grotto, swords drawn. With the use of a brass bell and his own fighting instincts, Blackbeard sustains only minor wounds in the quick battle, yet fails to discover who sent the assassins before they both die. While he recovers, Blackbeard eliminates Valentine from consideration due to their shared past and mutual respect. Santa Campana, however, condemns him - and Selima, ever distrustful, asks that they condemn Lowe as well.
Valentine and Lowe end up tied to a post in a makeshift prison. It's here that Valentine divulges to Lowe the meaning of a hellburner: an empty ship packed with gunpowder, set to detonate by a timing mechanism. In short, a weapon of indiscriminate destruction. Why does Blackbeard need hellburners? What does he want to destroy?
Without an answer, Lowe and Valentine head to the gallows, sentenced to death. Blackbeard arrives, intent on saving his friend... yet stops short of cutting him down himself, in service to the law established by the island's residents. After all, he says, he is not their king. That statement rings in the air as Valentine hangs by his neck... and Blackbeard exits the scene, a smirk on his face. Not missing a beat, Kate rushes to the gallows and asks Nenna to stave off Lowe's execution. Nenna hesitates, but agrees - and once again, Lowe avoids death. He later repays Valentine for his information by revisiting the gallows in secret... and putting an end to Valentine's long, painful death with a bullet to the heart.
Valentine's execution promotes his first mate Finnegan to captain, and Blackbeard proposes the chronometer scheme to him in kind. Finnegan wisely agrees to sell the chronometer to William Jagger in Jamaica. Selima sniffs out that this result was Blackbeard's plan all along, but not even she knows that he asked a woman at a brothel to instigate the assassination attempt with the two pirates. Blackbeard visits the woman and hands over an expensive jewel for her trouble, assuring her of the difference between legends and secrets.
At the other end of Santa Campana, Kate seeks out Lowe to thank him for talking to her husband. They share a tender, honest moment that soon turns to passion, and the two become entangled in a kiss...