Man’s Best Friend

A brilliant but ethically compromised scientist and owner of EMAX who conducts vivisection and genetic engineering. He keeps Max sedated with drugs but worries the effects will wear off, revealing a dangerous side. His pursuit of control and pride ultimately leads to a fatal confrontation in the lab.

An animal rights activist who plans to expose EMAX's cruelty. She forms a bond with Max and defies social expectations and Perry's opposition to the dog. Her loyalty to Max drives the plot, culminating in a dangerous stand-off at the lab.

A genetically enhanced dog created from multiple species, giving him strength, speed, and heightened senses. He is loyal to Lori but prone to violent rages when the drug effects wear off. His dual nature drives the film’s tension between protector and threat.

Lori's jealous boyfriend who wants Max kept in the backyard. His distrust and fear of the dog fuel conflict and push Lori toward drastic actions to find Max a new home. He ultimately suffers a brutal consequence at Max's claws.

An EMAX employee who seeks to reveal animal cruelty to Lori. She is killed by an animal attack before investigators can fully learn the truth. Her death marks the movie's early escalation into danger.

Judy's camerawoman who accompanies Lori during the break-in to document the lab's experiments. She helps capture the chaos that follows, a catalyst for the events that unfold.

The cynical junkyard owner who imprisons Max and is eventually killed by the dog during a brutal confrontation. He represents the human cruelty that Max repeatedly confronts.

A mugger who steals Lori's purse and is killed by Max, leading police to suspect the dog’s guilt. His murder precipitates the police pursuit.

A police detective who investigates the Max incidents and questions Jarret about the dog’s role in the killings. He embodies the law’s response to a rising sense of danger.

A police detective who collaborates with Bendetti in pursuing Max. His approach reflects the tension between protecting the public and recognizing the animal’s role.

A young neighbor whose collie Heidi is involved in the film’s animal dynamics. He represents the everyday life disrupted by Max's presence and the chaos surrounding the neighborhood.

Rudy's collie who shares in the neighborhood’s upheaval and later has puppies, mirroring Max’s genetic lineage in a symbolic twist.

The new puppy adopted by Lori and Perry, introduced after Max’s departure. Spike represents the attempt to move on from the danger and loss.