Thomas Roch

Engineer Serko

Engineer Serko acts as a manipulative overseer and technical handler of Thomas Roch, exploiting his genius.

Gaydon

Gaydon, secretly a French agent, feigns friendship and care for Thomas Roch to gain his trust and thwart the pirates.

Ker Karraje

Ker Karraje, the pirate captain, commands and controls Thomas Roch as a key asset for their criminal plans.

Simon Hart

Simon Hart, a pirate lieutenant, guards and monitors Thomas Roch, ensuring his compliance.

Ebba

Ebba feels pity and a strange fascination for Thomas Roch, viewing him as a tragic figure trapped by her father.

Captain Spade

Captain Spade is a pirate officer tasked with transporting and securing Thomas Roch.

Lieutenant Davon

Lieutenant Davon is a pirate guard who routinely watches over Thomas Roch.

Engineer Serko

Engineer Serko acts as a manipulative overseer and technical handler of Thomas Roch, exploiting his genius.

Gaydon

Gaydon, secretly a French agent, feigns friendship and care for Thomas Roch to gain his trust and thwart the pirates.

Simon Hart

Simon Hart, a pirate lieutenant, guards and monitors Thomas Roch, ensuring his compliance.

Lieutenant Davon

Lieutenant Davon is a pirate guard who routinely watches over Thomas Roch.

Gaydon

Gaydon, secretly a French agent, feigns friendship and care for Thomas Roch to gain his trust and thwart the pirates.

Healthful House

A French inventor of genius, now mentally unstable, confined to Pavilion No. 17 at Healthful House. He is obsessed with his fulgurator invention and guards its secret even in his madness.

Count d'Artigas

The mad French inventor, obsessed with his fulgurator, refuses to sell his secret for less than billions and exhibits signs of an impending fit.

III: Kidnapped

The target of the kidnapping; is incapacitated by a fit and lies on a sofa in the pavilion.

The Schooner Ebba

The missing inventor; the search of the Ebba fails to locate him.

V: Where Am I?

Fellow captive; Simon deduces he was also kidnapped, likely for his fulgurator secret.

On Deck

The inventor, visibly mad; fails to recognize Simon Hart, becomes agitated by the ship's movement, and suffers a violent fit.

Two Days at Sea

The kidnapped inventor; suffers a fit and is attended by Hart; his fulgurator is the likely motive for the kidnapping.

Back Cup

Mentioned as being placed in a similar compartment to Hart during the transfer into the tug.

X: Ker Karraje

Mentioned as the inventor of the fulgurator, which Ker Karraje seeks to obtain.

XI: Five Weeks in Back Cup

His mental condition improves; he is kept away from Hart and is being courted by Serko to reveal his fulgurator formula.

Engineer Serko's Advice

Works in his laboratory preparing the explosive; has not yet revealed the deflagrator's secret.

God Be with It

Works in his laboratory; his fulgurator is used to blast the tunnel.

Battle Between the Sword and the Tug

The inventor; is rescued from captivity but remains bound during the escape attempt.

XV: Expectation

Survived the collision and has returned to work in his laboratory; his fulgurator engines are being installed for defense.

Only a Few More Hours

Remains deluded, believing he is the rightful owner of Back Cup and its treasures, refusing to accept that he is a prisoner of pirates.

One Against Five

Initially launches engines to destroy a cruiser; refuses to fire on the French ship upon seeing the tricolor; crushes the phial and flees into the passage.

On Board the Tonnant

Moved by the sight of the tricolor flag, he deliberately caused the explosion that destroyed Back Cup, himself, and Ker Karraje's pirates.