Susan McAlester

Dr. Susan McCallister is the villain protagonist of the 1999 science-fiction horror film, Deep Blue Sea. She serves as the head of a team of marine biologists working at an ocean facility called Aquatica in hopes of finding a cure for Alzheimer's with the usage of brain tissues from sharks. Despite her good intentions, her questionable actions are what led to set off the plot in the film.

She was portrayed by Saffron Burrows.

History
Being a daughter of a Alzheimer's patient, Susan is constantly frustrated by her father's attempt to know why her mother isn't home, only for her to remind so many times that her mother died. She became bent on putting an end to Alzheimer's. After becoming a marine biologist and being the new head of Aquatica, Susan formulates a theory that enough protein complex residing from a Mako shark's brain tissue can produce enough neurons to increase membrane integrity and recuperate memory losses. However, she is distraught to learn that a mako shark's brain isn't big enough to produce enough protein for the test and that there is a code of ethics called the Harvard Compact which forbids anyone to use gene therapy for animal testing. Taking no regards in this, Susan secretly violated the code and used gene therapy to increase the brain mass on three Mako sharks, and had her best friend Dr. Jim Whitlock (who is one of the members of her team) to help her out. As a side effect, the three sharks became intelligent and dangerous, and Susan kept this as a secret to herself, not wanting her research to be shut down.

During the beginning of the film, one of the three sharks escaped captivity and attacked a boat full of teenagers, but shark wrangler Carter Burke (who is another member of Susan's team) arrives to the rescue and takes the shark back to its pen. The incident struck the news, and Aquatica's finances are put in risk. Despite this setback, Susan convinces her company to give her another chance of putting the test in so that they can use her new-found research so sell the cure for profit. To ensure of this, the company sends in one of their corporate executives, Russell Franklin, to Aquatica to personally investigate the facility and the experiment.

As Susan and her team start to enact their experiment, she had Carter to bring the largest shark into the lab by sedating it and putting it into sleep. As the shark is sleeping, Susan removes a certain amount of protein complex from the shark's brain. She then applied 2 CCs of the complex into a sample of inactive brain neurons of an Alzheimer's patient: the result was an increase of membrane integrity on the neurons by 6.5 seconds, much to the delight of the team. Though the test was a complete success, things get out of hand when Jim ends up being attack by the shark, who manages to chop off his arm, much to the shock of the others. Carter attempts to shoot down the shark with a shotgun, but Susan instantly releases it back into its pen, much to the anger of Carter, who calls her insane for doing this.

The team 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 in, causing it (with Jim on it) to fall into the pen waters. One of the test sharks grabbed the stretcher and instantly pull the cable, causing the helicopter to crash into the facility tower, killing both the helicopter pilots and the facility's tower operator Brenda Kerns. This also causes a complete blackout in the entire facility. The shark then used the stretcher to ram against an underwater window, and Jim dies of asphyxiation. As a result, the entire facility starts to sink slowly as the team tries to head up to the surface. During the journey, Susan is forced to confess her illegal tests on the sharks that caused them to be smarter and deadlier in the first place, resulting her entire team to be extremely furious at her for using them for her own needs. Despite her condolences over what happened, Susan tries to justify her actions, believing that her research could wipe out brain losses for future generations, but Carter retorts at this, asking her if the same would've been said for Jim, Brenda, and everyone else stuck inside the sinking facility.

As Aquatica slowly fills up, the three sharks start to target the team one by one. First, Franklin ends up being devoured by the big shark at the submarine deck while he was giving a motivational speech to the team. Next was another researcher named Janice Higgins, who ended up being devoured by the big shark while attempting to catch up with the team on the flooding maintenance ladder. Another one was researcher Tom Scoggins, who ended up devoured by the big shark while attempting to help Carter activate controls to drain the water away from a stairwell heading up to the surface. The only survivors left are Susan, Carter, and the facility's cook Sherman 'Preacher' Dudley.

After Preacher manages to kill the first shark by throwing a lighter into the kitchen's heating oven to blow it up, Susan starts to feels extreme guilt over her actions after being traumatized by the deaths of Franklin and Janice. She then tries to head over to her cubicle to retrieve some data regarding to her research, despite Preacher's warnings about everything they have gone through. Unperturbed by this, Susan heads over to her room to retrieve her data, but ends up being attacked by the second shark. Susan is then forced to kill the second shark by electrocuting with a power cable, but the reaction also destroys her data in the process, much to her distress.

Left with no alternative, Susan, Carter, and Preacher head over to a decompression chamber and swim over to the surface. Preacher then gets attacked and dragged on the leg by the third and final shark (presumably to be the big one), but he manages to swim himself to safety by stabbing the shark's eye with his crucifix, forcing it to let him go. After tending to Preacher's injured leg, Susan and Carter soon learn of a horrible revelation, 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 to be set free into the wild, Susan decides that she and Carter would have to kill it.

Carter devises 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 a 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 hands and dived into the water, causing the big shark to smell her blood. Susan then 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 distraught. 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 and connecting the wire to the battery, blowing the giant shark to bits and avenging the deaths of Susan and the rest of the team.