Gordeau commands Tarantula, a global assassin syndicate orchestrating assassinations, bombings, and massacres. His organization operates from a hidden Bermuda Triangle island, deliberately omitted from maps due to collusion with world governments exploiting Tarantula as a covert strike force. To enforce loyalty, Gordeau injects operatives with a poison tied to their tarantula tattoos, triggering agonizing death if they remain off-island too long without its unique volcanic gases. Physically, he bears a prominent tarantula tattoo across his bald forehead and wields a mechanical right hand functioning as an arm cannon.

Ruling through fear, Gordeau epitomizes chronic betrayal, showing no loyalty even to subordinates. He disciplines underperformers by using them as live training targets. His ultimate scheme involves massacring Tarantula to plunder gold beneath the island. He manipulates defectors like enslaved Ellen and her brother, promising an antidote while plotting their deaths. Collaborating with Doc—his accomplice and Lupin III’s former partner—he swaps genuine gold shipments for counterfeits. This deception ignites a lethal clash between Ellen’s rebels and loyalist assassins, causing widespread casualties.

Gordeau’s treachery culminates in his demise. After securing the real gold, he attempts solo escape, having given Doc a fake antidote. Doc, anticipating betrayal, shoots Gordeau point-blank as the toxin wracks his body. This act underscores Gordeau’s moral bankruptcy and the self-destructive cycle of his deceit. His leadership prioritizes absolute control and personal gain at all costs, directly causing tragedies including Ellen’s enslavement and her brother’s murder—a truth Doc weaponizes for psychological cruelty.