The Mako Sharks are the main villains of the 1999 sci-fi horror film Deep Blue Sea. They were genetically engineered to harvest protein complex for a cure for Alzheimer's, but they were later shown to be more intelligent, deadly and dangerous than spoken.
Origins[]
They were genetically engineered by Susan McCallister and Jim Whitlock of the Aquatica facility to produce protein complex from their brains that will serve as a cure to reactivate human brain cells. According to one of the researchers named Janice Higgins, the team used a hormonal enhancer to increase the sharks' brain five times the normal size. However, it turns out that Susan herself used gene therapy to increase the brain mass, which is considered a violation of a code of ethics called the Harvard Genetics Compact. As a side effect, the sharks become more smarter and dangerous than ever. This also allows the sharks to develop an ability to swim backwards, which something that a normal shark can't do and developing a taste for other shark species, such as the time when the crew released a tiger shark into the test sharks' pen, whereupon the test sharks instantly devoured the tiger shark.
Role[]
In the beginning of the film, one of the Mako sharks escaped captivity and attacked a boat full of teenagers, but fortunately, expert shark wrangler named Carter Blake (one of the members of the team and the main hero of the film) arrives to the rescue and brings the shark back to its pen. This incident puts Aquatica's finances at risk, so Chimera Pharmaceuticals (the facility's main sponsor) sends in their board president named Russell Franklin to investigate the facility. When the day of the test is about to begin, Susan had Carter to round up the largest shark into the lab. After having it sedated and put to sleeping, Susan extracts the protein complex from its brain and applied two CCs of it onto a sample of inactive brain neurons of an Alzheimer's patient. The result was a complete success as the cells start to reactivate and maintain membrane integrity in 6.5 seconds. However, things get out of hand when Jim ends up having his left arm chopped off by the big shark. Carter then attempts to shoot the shark with a shotgun, but Susan releases it back into its pen, much to Carter's anger.
The crew then calls in a paramedics helicopter to evacuate Jim for medical attention, but a strong hurricane made it too difficult for the pilots to reel the stretcher, causing the stretcher (with Jim on it) to fall into the pen waters. The big shark then grabs the stretcher and pulls the cable, causing the helicopter to crash into the facility's tower, killing both pilots and the tower operator named Brenda Kerns. This also caused a complete system shutdown in the entire facility. The shark then uses the stretcher to ram against a underwater window, and Jim dies succumbing to asphyxiation just as the facility slowly starts to flood. The sharks also proved to be strong enough to break down steel doors with a single hit, which is considered unusual. At that point, Susan is forced to confess that she and Jim performed illegal experiments on the sharks, causing the other members to be very furious and aggravated at her for this.
As time goes by, many of the members end up being attacked by the sharks one by one. Russell Franklin was the first one to be devoured as he was giving a motivational speech to the team at the submarine deck. The second was Janice Higgins, who ended up being devoured while trying to catch up with the team climbing through the flooding maintenance ladder. The third was Thomas "Tom" Scoggins, who ended up being devoured while trying to help Carter activate some controls to drain the water from a stairwell leading to the surface. The only three survivors left are Susan, Carter, and the facility's chef named Sherman "Preacher" Dudley.
Preacher managed to kill the first shark by throwing his lighter at the kitchen's heating oven to blow it up after it ate his beloved pet parrot. Susan managed to kill the second shark by electrocuting it with a power cable, at the cost of destroying her remaining research in the process. As Susan, Carter, and Preacher finally head up to the surface, Preacher ends up being attacked and dragged on the left leg by the third and final shark (presumably the big one), but he manages to swim to safety by stabbing the shark's left eye with his crucifix, forcing it to let him go.
After tending to Preacher's injured left leg, Susan and Carter learn of a horrible realization: the sharks have been herding the team into flooding the facility so that they could escape through the plain steel fences at the surface into the open deep blue sea. Realizing now that the big shark is too dangerous and deadly to be set free into the wild, Susan decides that she and Carter would have to kill it.
Carter devised a plan to kill the big shark: he would fire a harpoon filled with dynamite powder at the shark, and that Susan would have to connect the trailing wire to a car battery that will send in an electric current to blow it up. However, the big shark is too far away and too deep for Carter to make a clear shot. In a last-minute effort to get the shark's attention, Susan cuts her left hands and dives into the water, causing the big shark to smell her blood. Having attracted the shark's attention, Susan tries to climb out, but the ladder breaks, and despite Carter's attempt to save her, the giant shark devours Susan whole, much to Carter's distress. Despite Susan's death, her effort was enough for Carter to get the shark at firing range, allowing Preacher to fire the harpoon at the shark's dorsal fin, though it pierced Carter's left leg in the process. As the giant shark finally attempts to swim out to the open sea, Carter frees himself from the harpoon as Preacher connects the trailing wire to the battery. As a result, the giant shark blows up to pieces, avenging the deaths of the rest of the team, much to both Carter and Preacher's relief. With the sharks now gone for real, Carter and Preacher reunite in the wreckage of the facility as they await for an incoming boat en-route on the horizon.
Personality[]
Even while they still instinctive and regular sea predators, these sharks were obviously savage, sadistic, merciless, resentful, and vituperative toward Aquatica scientists for their experiment on them. As stated from Russell and Carter's conversation regarding what Mako Sharks wanted much later in the film, it is revealed that all this time, the sharks also missed their freedom, but were too helpless with their current state prior to being given gene therapy. Once given gene therapy on their brains that enhanced their intelligence, this ultimately enhanced the Mako sharks' awareness about their surroundings and they became more resourceful than ever. The largest shark revealed its enhanced awareness by chop off Jim's arm when the latter lowered his guard. The largest shark even threw a stretcher on the underwater window's glass so water would flood the whole facility as they were aware that the cannot stalk on humans without water to breathe with their gills. Given that they were choosing to killed all humans first before fleeing to the open sea, such as Yellow Sea and it is implied the three Mako sharks believed that they would not be free as long as the humans in Aquatica were still alive. Unfortunately, this also led to their downfall.