Scooby-Doo! Pirates Ahoy!

While charting the Bermuda Triangle, Rupert Garcia's ship is besieged by ghost pirates led by Captain Skunkbeard. He hides from them, but the pirates sink the vessel and kidnap his crew, leaving him adrift at sea. Garcia warns of a looming danger even as the pirates disappear.

Fred Jones treats his friends to a mystery cruise arranged by his parents for his birthday. Shaggy and Scooby encounter a cloaked man before meeting cruise director Sunny St. Cloud and Captain Crothers. The mood on board is light, with the promise of adventures ahead.

During the voyage, Mystery Inc. quickly solves all of the mysteries set by St. Cloud, inadvertently irritating other passengers. Their success highlights the gang's skill and upsets the flow of the cruise's supposed mystery entertainment. The crew remains curious about the sudden competence of the sleuthing duo.

Mystery Inc. rescues Garcia from the wreckage and he warns them of pirate danger. The group initially suspects this is yet another staged mystery by St. Cloud and opts not to intervene. Garcia's urgency plants the seed for a real threat to their voyage.

Eccentric billionaire Biff Wellington arrives on a jetpack to refuel for his around-the-world record attempt. His flamboyant entrance adds a distracting spectacle to the voyage. The crew and guests take notice of the growing disruption.

At a costume dinner, the cloaked man reveals himself as Mister Mysterio, a famous hypnotist. He uses his powers on Shaggy and Scooby as volunteers, but the audience is briefly drawn into his trance before he undoes the hypnosis and departs. The moment foreshadows the ship's later danger.

Skunkbeard's pirates launch a brutal attack on the ship, causing passengers to vanish and kidnapping Fred's parents. The vessel sinks, forcing Mystery Inc. to fight for survival amid wreckage. Garcia is found among the chaos and the gang escapes with him.

The glowing trail left by the pirates leads Mystery Inc. to a deserted island harbor where Garcia's ship is hidden. Before they can regroup, the pirates recapture the group, including Skip, and take them deeper into the island's secrets. Tension rises as plans to thwart the pirates begin to take shape.

Skunkbeard reveals that the Bermuda Triangle's power source is a meteor that fell to Earth 200 years ago, and he forces Garcia to help locate it. The pirates recruit Mystery Inc. and the captive Skip, deepening the stakes for everyone aboard. The crew realizes the treasure hunt is really a dangerous plan for control of a strange power.

The pirates reach the triangle's heart and confront the ghosts of its past victims, while Mystery Inc. works to uncover the illusion behind the haunting. They use a crane to dredge the meteor from the seabed, unlocking the mystery of the triangle's power. The moment blends myth and science as the heroes prepare to act.

Mystery Inc. discovers modern equipment projecting the ghosts and builds a trap to subdue the pirates. They unmask Skunkbeard as Wellington, his first mate as Mysterio, and reveal the other pirates as passengers and crew. Mysterio admits hypnotizing everyone to aid in retrieving the meteor, which turns out to be made of gold.

A tectonic reaction is triggered by the meteor, confirming its link to the triangle's power. The gang decides to return the meteor to the sea to avert catastrophe, then makes their escape. The immediate threat subsides as the wrecks drift away into the sea.

The group commandeers Mysterio's galleon to head home and subdues Mister Mysterio and Wellington. Captain Crothers calls the authorities to ensure their arrest upon arrival, bringing the adventure to a close as the ship approaches land. Mystery Inc. returns as heroes with a wild tale of treasure and trickery.