Man’s Best Friend

Judy Sanders, an EMAX employee, contacts television personality Lori Tanner to arrange a post-work meeting. She intends to show Lori the atrocities and animal cruelty allegedly occurring in EMAX's laboratories. The plan sets the stage for what is to come.

As Judy returns to work, an animal assailant attacks and kills her. EMAX owner Robert Jarret then sedates the attacker, revealing his involvement in vivisection and genetic engineering. The killing shocks the immediate aftermath and sets the plot in motion.

Lori Tanner and her camerawoman Annie infiltrate the EMAX laboratory, filming the experiments on animals. They free a Tibetan Mastiff named Max and escape with him. Jarret immediately reports the dog stolen to the police, making Max effectively a fugitive.

Jarret tells police that Max has been stolen and discloses that Max is a genetically altered dog, spliced with DNA from big cats, snakes, and other creatures. He notes the dog’s enhanced abilities and propensity for violence. He fears the drug he uses to calm Max may wear off.

Unleashed by the recent escape, Max terrorizes the neighborhood. He scares a paperboy, devours a cat and a parakeet, chews through the brakes of Perry’s car, and kills a mailman. The dog’s rampage demonstrates his dangerous combination of strength and ferocity.

Despite the danger, Lori grows attached to Max and forms a bond with him, believing he understands human conversation. Her relationship with Max is strained by Perry’s insistence that the dog stay in the backyard. Max shows intelligence and loyalty, complicating her view of keeping him.

Police question Jarret about Max and learn of the dog’s engineered mutations. Jarret explains the genetic splicing and the drug regimen used to keep Max calm, acknowledging the looming risk when the supply wears off. The confrontation underscores the moral nightmare behind EMAX's experiments.

Max’s violence intensifies as he roams the streets when Lori isn’t around. He attacks and destroys more domestic animals, and his ferocity remains a looming threat to the community. Lori’s and the police’s attempts to stop him become more urgent.

To keep Max away from Lori’s life, she leaves him with Ray at a junkyard, who promises to ship him to a ranch. Ray chains Max to a wall and beats him with a shovel to quell his barking, only to be overpowered and killed by Max when he fights back. Max returns home scarred and more dangerous.

Perry departs and a new puppy, Spike, is introduced to replace Max. Enraged by the betrayal, Max marks his anger on Perry with a spray of acidic urine, burning his face, and then attacks Lori before the police arrive. The incident marks a turning point in their uneasy truce.

After the attack, the police arrive intent on stopping Max at any cost. Max escapes but continues to elude capture, raising the stakes for everyone involved. Lori’s cooperation becomes crucial as the manhunt intensifies.

Jarret abducts Lori and the puppy Spike, hoping Max will follow to the EMAX facility. Max does trace them to the lab, drawn by a mix of loyalty and need for closure. The trap culminates in a dramatic confrontation in the laboratory.

Inside the lab, Max’s aggression softens and he approaches Lori’s hand, but Jarret shoots him with a shotgun. Max is knocked into an electrical cage that kills Jarret, and Lori tends to Max as he dies.

Three months pass after Max’s death, and Rudy’s collie gives birth to a litter of puppies. Most resemble their mother, but one black puppy stands out, bearing an uncanny resemblance to Max. The film ends with a hint of Max’s legacy living on.