In Sinbad, Legend of the Seven Seas, the alluring Goddess of Discord, Eris, plots to wreak havoc on the Twelve Cities, which are safeguarded by the enchantments of the coveted Book of Peace. This precious tome is being transported by ship to a secure location in Syracuse by Prince Proteus, the only son of King Dymas. However, their journey is intercepted by the daring childhood friend Sinbad and his shipmates. Sinbad's crew, comprised of his loyal lieutenant Kale, lookout Rat, and the entertaining oriental twins Jin and Li, create a chaotic scene where they aim to seize the Book for ransom.
As their voyage continues, Eris unleashes the ferocious sea monster, Cetus, to attack their vessels. Though both Sinbad and Proteus manage to defeat the beast, Sinbad finds himself adrift, where Eris attempts to persuade him to steal the Book in exchange for untold riches—a tempting offer that draws laughter from his skeptical crew when he relays the story.
Safely reaching Syracuse, the celebratory feast turns sour when Sinbad crosses paths with Marina, the fiancée of Proteus and the woman he secretly loves. Following a series of deceitful acts, Eris infiltrates the tower safeguarding the Book, cleverly disguising herself as Sinbad to thwart the guards and make off with the tome, leaving Sinbad framed for the crime. Chaos soon engulfs Syracuse, and Sinbad is unjustly sentenced to death. Yet, Proteus, harboring faith in Sinbad's innocence, pledges to take on Sinbad's punishment, buying him crucial time to recover the Book.
Determined to rescue Proteus, Sinbad sets out on a perilous journey aboard his ship, the Chimera, with Marina tagging along after bribing Sinbad with jewels. As they navigate treacherous waters and face trials—including enchanting but dangerous siren songs that mesmerize Sinbad's crew—Marina proves to be an asset, skillfully guiding the ship through the roughest challenges.
Their escapades grow more perilous when they land on a seemingly tranquil isle that turns out to be a colossal fish. Amidst their struggles, events swirl them into deeper danger as Eris intervenes once more, entangling them in a battle against freezing ice and a fierce Roc. Escape leads to a blossoming connection between Sinbad and Marina, but time is running out.
Upon reaching the brink of Tartarus, Eris reveals her true scheme—to secure the Book while plotting Proteus' downfall. Sinbad must confront a dilemma: will he escape with Marina or face execution? His answer costs him dearly, resulting in both he and Marina being tossed out of Tartarus. As Syracuse awaits Proteus' fate, Sinbad's arrival brings about unforeseen heroics that restore peace but at a personal cost.
In a twist of fate, as they sail into the sunset, Marina joins Sinbad, and together they seek adventure on the high seas. An additional post-tale on the DVD reunites them in a thrilling battle against blue furry Cyclops on the mysterious isle of Krakatoa, leading to an unexpected volcanic eruption that leaves viewers on the edge of their seats.
