Upon possessing a young woman named Meg Masters (
Nicki Aycox), the demon assumes her name and tracks down series protagonist
Sam Winchester in the first season episode "Scarecrow". The two briefly meet while hitchhiking—Sam left his brother
Dean to track down their missing father
John—and then again at a bus station. Despite her attempts to convince him otherwise, Sam eventually leaves to help Dean with one of their supernatural investigations. Meg slits a man's throat and uses his blood to communicate with her father
Azazel, the demon responsible for the death of Sam and Dean's mother. Sam encounters her again in the episode "Shadow". Finding her reappearance suspicious, Sam spies on her and realizes that she is responsible for recent deaths of natives from his hometown. The brothers confront Meg and learn that the murders were actually a trap set for John, who has been hunting Azazel. After Sam and Dean reunite with John and acquire the demon-killing
Colt, Meg begins killing their friends in "Salvation" and threatens to continue doing so unless they surrender the weapon. John delivers a fake gun, but Meg and her demonic brother take him hostage after quickly realizing the deceit. Meg tracks down the brothers in search of the Colt in the season finale "
Devil's Trap", but is ultimately captured and
exorcised to Hell. Meg escapes Hell in the second season and takes possession of Sam (
Jared Padalecki) in "Born Under a Bad Sign", seeking revenge against the Winchesters. To trick Dean into killing his brother, she uses Sam's body to kill one of the Winchesters' fellow
hunters before taking their friend
Jo Harvelle hostage, attempting to convince Dean that Sam has succumbed to Azazel's influence and can't control his actions. However, Dean and the Winchesters' ally
Bobby Singer realize that Sam is possessed, and despite Meg's attempt to seal herself in Sam using a binding link, she is forced to flee Sam's body once she becomes vulnerable to exorcism after Dean and Bobby burn the mark off. Meg returns in "Are You There, God? It's Me, Dean Winchester" and is one of the spirits that haunts Dean, Sam, and Bobby. After the demons' god
Lucifer is freed from Hell, Meg (
Rachel Miner) resurfaces in the fifth season premiere "Sympathy for the Devil" to try to kill Dean (as he is believed to be the one who will kill Lucifer) before he can find a weapon said to be capable of killing Lucifer. Her attack leaves Bobby paralyzed, but she is forced to flee when Dean tries to kill her. She returns in "Abandon All Hope..." and sends a pack of hellhounds after Sam, Dean, and their friends Jo and
Ellen Harvelle when they arrive to kill Lucifer; the confrontation ends in Jo and Ellen's deaths. After Lucifer captures the angel
Castiel, an ally of the Winchesters, Meg stands guard over the prisoner until he escapes by pushing her onto the burning circle keeping him trapped, allowing him to walk over her to escape. The Winchesters ultimately send Lucifer back to Hell at the end of the season. The demon
Crowley assumes reign, forcing Meg to go into hiding as a Lucifer loyalist. When Meg's forces capture Sam and Dean in the sixth season episode "Caged Heat" to find and kill the new ruler, Sam recruits her to torture Crowley until Crowley agrees to restore Sam's soul. Once Castiel seemingly kills Crowley upon the latter's admitting he can't restore Sam's soul, Meg flees before the Winchesters have the chance to kill her, too. Crowley is later revealed to have faked his death. Meg reforms her alliance with Dean in "The Born-Again Identity" in order to stop Crowley from capturing Castiel. After Castiel absorbs damage Lucifer previously caused to Sam's mind, the Winchesters leave a now-insane Castiel in a mental hospital and Meg takes a job at the hospital to watch over him, reasoning that her status as a Lucifer loyalist marked her as Crowley's enemy and it is thus in her best interest to help the Winchesters. When Castiel partially recovers in "Reading is Fundamental," Meg alerts the brothers and later helps protect Castiel from both angels and demons. In the seventh season finale "Survival of the Fittest", Crowley finds her with Sam, Dean, and Castiel, but does not take action against her because it would upset Castiel, who is necessary to bringing down the
Leviathans. Meg assists the Winchesters in killing
Dick Roman, the leader of the Leviathans, by directly attacking Dick's headquarters and thus distracting his forces. However, Crowley has her captured immediately afterwards. He tortures her for the location of Lucifer's crypt, which holds a Word of God tablet about angels Crowley wants. Castiel and the Winchesters rescue Meg in the eighth season episode "Goodbye Stranger", and she takes them to the crypt's location. When Crowley arrives, Meg sacrifices herself to allow Sam, Dean, and Castiel time to escape with the tablet. In
season 15's "Destiny's Child," the Shadow, the ruler of the Empty, takes on Meg's form to communicate with Castiel, greeting him with Meg's traditional "Hello, Clarence" and adopting some of her mannerisms. Later, in "Unity," the Shadow once again appears as Meg in Death's Library. When Sam sees "Meg," he is confused until the entity explains that it is borrowing Meg's form due to its lack of one and it states that the real Meg is still dead. The Shadow then appears as Meg to Jack in "Despair" while they are both in the Empty. ==Characterization==