The Beast of Bray Road

Kelly reveals that she was bitten by another werewolf, implied to be the actual Beast of Bray Road. While she initially learned to control her transformations and only changed during the full moon, she eventually lost control of the ability, causing her to attack and kill people.

Earlier scenes show Kelly acting erratically and having unexplained injuries, hinting at her dual nature.

After pursuing the wounded Beast to the Roadhouse, Phil notices Kelly has an injured leg that matches the Beast's wound from being shot. This visual clue, combined with the timing and location, leads him to confront her about being the creature.

The timeline shows Phil chasing the Beast directly to the Roadhouse where Kelly is located.

According to the film's mythology, silver is the only substance that can nullify a werewolf's regenerative powers. When Billy loads his guns with silver bullets, they become capable of actually harming and eventually killing the Beast, whereas regular ammunition would simply heal around the wounds.

Both Phil and Billy become infected with lycanthropy - Phil from being bitten by Kelly, and Billy from being bitten during the earlier attack. They sequester themselves in the mountains with a supply of Quinn's anti-werewolf serum, which offers hope for controlling their condition rather than curing it.

Quinn brews a serum from nightshade and Wolfsbane, which he describes as the Ebola virus for werewolves. When Phil injects Kelly with it while she is partially transformed, it forces her back into human form, temporarily negating her werewolf abilities and giving the hunters time to regroup.

Kelly tells Phil that while she initially mastered the ability to transform only during full moons, she has recently lost control of it. This suggests the curse progressed or strengthened over time, making her transformations involuntary and increasingly dangerous.

The dashcam from Deputy Dennis Snarski's police car provides concrete proof that the Beast is a werewolf. After Dennis is killed by the creature, the footage is recovered and analyzed, confirming the supernatural nature of the predator and allowing the team to adjust their hunting strategy accordingly.

Kelly manipulates Pamela into believing she needs to shoot Phil by tricking her during the chaos of the confrontation. Once Pamela is distracted, Kelly attacks and kills her. This betrayal demonstrates how the werewolf's influence has corrupted their team from within.

The Beast is defeated through a combined effort: Billy sets Kelly on fire while she's distracted murdering the arriving motorists, weakening her with the flames. Then both Billy and Phil shoot her with silver bullets, finally overcoming her regenerative abilities and killing her.

Deputy Dennis Snarski is killed by the Beast while investigating the attacks. His death is significant because his police car is later recovered, and the dashcam footage inside provides the first concrete proof that the creature is a supernatural werewolf.