Captain Barracuda is a seafaring thief with some behaviors of a stereotypical classic pirate, stealing from anyone that crosses his path on the high seas. His attempt to rob a Gotham Boat Line cruise ship sailing around Manhattan was foiled by two passengers: the Fantastic Four's Human Torch (Johnny Storm) and the X-Men's Iceman (Bobby Drake). Barracuda's craftiness kept his enemies at bay by repeatedly tricking them into using their powers against themselves, and eventually Torch inadvertently started a fire on the ship's deck. The heroes battled the blaze and captured his men, and when Barracuda attempted to escape with a hostage, Storm's girlfriend Dorrie Evans, the heroes left him stranded in his boat atop a tall ice mound awaiting incarceration.
Seeking to purloin a new type of atomic warhead aboard a military bomber aircraft, Barracuda resurfaced near the Florida coast in a pilfered seacreature shaped submarine and stumbled upon Atlantean ruler Namor locked in combat with Karthon the Questor for the Lemurian Serpent Crown. Barracuda captured Namor, Karthon and the Crown, intending to torture them until he learned all about the headpiece, then returned to his original goal. Barracuda destroyed the plane, stole the warhead and threatened to use it against a US naval lookout station as blackmail for a large payoff. His first mate, Mr. Starkey, unintentionally helped Namor escape, but Barracuda fired a torpedo at unsuspecting sailors, framing Namor for the act despite him stopping the torpedo while Karthon swam off with the Crown. With the Naval fleet’s attention diverted toward Namor, Barracuda went ashore to steal the Omni-directional Beam, a device able to change the direction of any torpedo. He returned to his submarine but accidentally activated the device, redirecting a torpedo chasing Namor toward his own vessel, seemingly killing himself and his crew.
Both Barracuda and Mr. Starkey survived, taking refuge in an undersea base once belonging to another seafarer, Captain Nathaniel Omen, and electronically intercepted numerous distress radio transmissions from scientist Dr. David Purvis explaining a mishap dealing with a gamma-ray powered machine able to devolve humans into ape-like beast-men. Searching for the machine, Barracuda identified a gamma source on the ship DMB Rotterdam, attacked and boarded it, but only found the gamma-irradiated Hulk (Bruce Banner) working as a deckhand. Barracuda fled, continuing his search, and later encountered Hulk again on the island where Purvis had been stranded for years along with the machine and several devolved colleagues. After a brief scuffle, Barracuda kidnapped Purvis and stole the machine, returning to his sub-sea cavern where he tested the device on Purvis, transforming him into a beast-man. Hulk followed and rescued Purvis, but they were outnumbered by Barracuda's men. An enraged Hulk sought to destroy everything and damaged the base's main power conduits, overloading the power plant. Barracuda used the machine against Hulk, reverting the Hulk to Bruce Banner and rendering him unconscious. Although appearing unintelligent, the ape-like Purvis knew friend from foe and attacked Barracuda before using the machine to devolve Barracuda’s crew and returned Banner to the surface just before Barracuda’s base exploded, seemingly killing everyone inside.
Having escaped in his submarine, Captain Barracuda next sought revenge on Namor. He invaded Atlantis and stole the Proteus Horn with which he commanded hordes of sea-monsters to march on New York City while he looted a bank. Drunk with power and believing the Horn would allow him to conquer the world, Barracuda abandoned his scheme to rule the seas. Unwilling to share his conquests, he dismissed his crew, so that they refused to help him against the Fantastic Four's Invisible Girl (Susan Richards) when she chanced across them. The Fantastic Four aided Namor in driving the monsters back to the deep, reclaiming the stolen Horn and detaining Barracuda until the police arrived. Barracuda eventually recovered the Horn after it was lost at sea during a battle with the Fantastic Four.
Years later, Barracuda returned armed with the Glove of Asteria, an artifact previously housed at Project PEGASUS that had wound up on the black market. Along with his gang, the Black Mast, he hijacked several oil tankers, taking hostages; their flagrant disregard for human life forced the American government to call in specialists to take them down. Steve Rogers' "Secret Avengers" team separated Barracuda from the glove, but before being defeated, Barracuda used the Proteus Horn to summon several gigantic sea-monsters. While the Avengers retreated with the surviving hostages, Barracuda was left behind and dragged under the waves caused by the creatures.