Megan

"Being nice to women will get you nowhere, Cooper. Being nice to me will get you killed. You may think they're all bitches, but... I'm the real thing! Do you think I like being part of this fucked-up family?! Do you think I chose to run with the pack? No! I chose you. But now you're out of luck, and I'm out of time. And all we can do is let nature take its course."

- To Cooper

Megan was seemingly a zoologist living in the next glen over from the Uath family's who's studied the werewolves and aided the squad in taking refuge at the family's farmhouse. In actuality, she was one of the werewolves, having been forcibly adopted into the family and suppressing her transformation for most of the night.

Biography
Megan, as a Zoologist, visited the Scottish Highlands in order to investigate the rumours of werewolves in the area. It is implied that during a full Moon, the Werewolf Family there attacked and infected Megan with the curse and then took her in. When Captain Richard Ryan and his team first visited the glen, they attempted to have Megan be their guide.

During one full Moon, while the rest of the family transformed, Megan was somehow able to supress the transformation. When the other werewolves attack a squad of soldiers in the Highlands, Megan, mistaking the soldiers for a rescue team, helps them escape back to the Werewolf Family's cottage. Apparently she despises the Werewolf Famiy and desires to escape them.

Megan uses her knowledge on werewolves to aid the soldiers in fighting off the creatures' attacks, and also helps treat Sergeant Wells' wounds. Upon learning they are not there to get her out, Megan gives up and tricks the soldiers into destroying their only means of escape by convincing them to use the family's Land Rover to blow up the barn which she claims the werewolves are hiding in. Megan then reveals the truth about herself, and that whilst the squad was occupied destroying the barn she'd unlocked the doors and let the other werewolves into the house. No longer able to suppress her transformation, she gives in, but is shot in the eye by the Sergeant mid-transformation.

However, Megan survives the gunshot and fully transforms, though her left eye remains missing. . She is among the three werewolves who enter the kitchen after Cooper and the Sarge blast into it through the ceiling, finding the Sarge alone and approaching him as he begins transforming. When the Sarge raises a lighter attempting to ignite the gas he's released, Megan brutally swats the lighter out of his hand - moments before the Sarge triggers the oven, causing a flame which blows up the entire house and kills the werewolves inside.

Personality
Megan's behaviour towards the squad experienced subtle shifts, hinting at her deceit. When first she encountered them on the country road, she immediately moved to help them escape the attacking werewolves, and had a relatively-positive attitude. But when she discovered shortly afterwards that they weren't a rescue mission and were just more hapless "lambs for the slaughter", crushing her secret hopes of escaping the Uath's, she acted more dour from then on. She also displayed a sarcastic side around Cooper. For the most part, Megan took an encyclopaedic role among the survivors holed up in the farmhouse, providing them with information and seeming theories about how the werewolves would operate. Despite this, she unintentionally gave more subtle hints that she wasn't who she said she was; such as when she let slip that the soldiers ran into her on the road instead of vice versa (as observed by Ryan), and when she snapped at Ryan, then immediately tried to distract Cooper from his roused suspicion by reminding him they didn't have to wait long until sunrise. Megan was also unafraid to share her blunt explanation that the soldiers were being attacked by real-life werewolves despite knowing they'd initially meet it with ridicule.

Though Megan ultimately aided the Uath werewolves, she despised being part of their "fucked-up family", and wanted to escape despite her werewolf condition. To this end, she repressed her transformation and hid the truth about herself to the squad, aiding them in the hopes they'd be her way out when she still believed they were sent on a search-and-rescue mission - she remained hidden among them after finding out this was not the case. However, despite her actions' selfishness, Megan wasn't immoral so much as desperate, sincerely apologising to Cooper upon revealing herself after the barn's destruction. After losing hope of escaping, she became bitterly resigned.

Megan appeared to reciprocate Cooper's interest towards her when helping him take Sergeant Wells upstairs, and when allowing him to treat her injured hand. Whether this was genuine or merely part of her cover is unknown, although she genuinely cared for his feelings when revealing herself, and was quite bitter when Cooper responded to her betrayal by deeming her part of women's "same old shite." Megan also didn't appreciate Cooper's misogyny immediately afterwards, icily making a jibe about "that time of the month." She genuinely cared for Sam, being attentive towards him after her Land Rover's destruction, and taking a steely attitude towards Ryan after the latter nearly attempted to shoot Sam.

Trivia

 * While working to stop Wells' squad from escaping the werewolves, Megan appeared to communicate with the werewolves outside when she was alone. With them apparently telling her to trick them into destroying the barn.
 * She can play the piano.