Frank Walsh, portrayed by Nicolas Cage, is a seasoned big-game hunter for zoos who embarks on a perilous journey across the ocean aboard a ship. This ship is not just any vessel, as it carries a notorious criminal, Richard Loffler, played by Kevin Durand, who has been apprehended by the FBI for heinous crimes, including the murder of a U.S. Senator. Frank has recently captured a rare white jaguar, a creature the local populace deems an evil spirit worthy of human sacrifices to protect their village.
As Frank prepares to transport his valuable catch to the United States, he encounters complications due to Loffler and his own ambitions. Dr. Ellen Taylor, a dedicated neurologist played by Famke Janssen, accompanies Loffler to monitor his precarious mental condition, knowing that atmospheric pressure changes could prove fatal for him. During a conversation in the ship's cafeteria, Ellen urges Frank to relinquish the jaguar to the endangered species bureau instead of auctioning it off for a million dollars.
The situation spirals out of control when Loffler cunningly fakes a seizure, kills his guards, and escapes. Tasked with recapturing him is John Ringer, portrayed by LaMonica Garrett, leading a team of FBI agents. In the chaos, Richard frees some of Frank's captured animals, including dangerous monkeys, which wreak havoc as they attack the ship’s crew. Loffler uses a radio stolen from the guards to taunt Frank, revealing shared military backgrounds and lamenting how the military turned him into an assassin before casting him aside.
As Richard unleashes further mayhem, even stopping the water pumps and letting venomous snakes loose, he seizes control of the ship's command. In a dramatic turn, he eliminates Ringer and most of his FBI team, escalating the conflict. Frank, desperate to retrieve the jaguar—a unique opportunity he can't afford to lose—refuses to abandon ship. Tensions rise when Paul Freed, played by Michael Imperioli, is revealed to be an insider aiding Loffler, providing crucial intelligence for the criminal.
With the ship’s engines disabled to prevent Loffler's escape to the Caribbean, Richard cleverly impersonates Ringer to call the Coast Guard for assistance. In a climactic confrontation, Frank discovers Loffler now holds Ellen hostage, leading to a showdown, where Paul’s betrayal and motivations come to light. A grim battle ensues, resulting in injuries for both men. Ultimately, Frank manages to turn the tables by incapacitating Loffler with a neurotoxin dart, capturing him in a noose, and unleashing the white jaguar for his final act of vengeance.
As the Coast Guard arrives, the vessel's captain inquires about the animal transport permits, and Ellen skillfully covers for Frank by claiming that Loffler destroyed the paperwork, ensuring their escape while concealing the chaos that unfolded aboard the ship.
