It is the directorial debut of Emile Edwin Smith and stars Christopher Judge and Elisabeth Röhm, with Debbie Gibson reprising her role as Emma MacNeil from the first film.

The Mega Shark begins its reign of terror by flipping the tugboat to the air until it crashes and decapitates the Sphinx hundreds of miles away in Giza.

At Pearl Harbor, Jack Turner and Rosie Gray are assigned to pilot the Mecha Shark, a new prototype submarine that resembles the megalodon.

Later, aboard the USS Charles Davis, Admiral Engleberg is warned by Dr. Emma McNeil that the megalodon's aggression attributes to its search for a mate.

Jack and Adm. Engleberg tell the James Stewart crew to turn off her emitters; the attack is briefly halted, but the megalodon jumps to intercept a fighter plane and crushes the carrier in the process.

After the Mecha Shark returns to the Charles Davis, Jack and Adm. Engleberg argue over putting an unconscious Rosie back in the field when Nero suggests it can control the submarine by itself.

Nero once again malfunctions; this time, the Mecha Shark enters Drone Mode, a fail-safe system programmed to complete its task without the safety protocols.

Jack rushes to Sydney and reunites with Rosie, but Mecha Shark goes back online and determines all humans in sight as hostile after soldiers point their guns at it.

As the Mecha Shark goes into amphibious mode and terrorizes the streets, Emma calls Rosie and suggests to lure it back into the ocean and convince the megalodon to destroy it.

Jack and Rosie leave the Mecha Shark before the megalodon bites the left side of the submarine, triggering a dislodged torpedo which destroys both combatants in the explosion.

Although the Asylum is known for low-budget "mockbusters",[6] the company places great importance in its scripts; Prendes made a total of nine drafts of the screenplay in two months due to the many notes given to him by producers.

The Blu-ray release includes an audio commentary by director Emile Smith, writer Jose Prendes, and actor Christopher Judge, a six-minute "Making Of" featurette, a gag reel, and previews of other films by the Asylum.