|Dates||1978/79 - 2008 (killed by Sam Winchester)|
Jack Montgomery is a rugaru, a monstrous cannibal creature that can appear human for years before it "turns." Jack's father was also a rugaru, killed by the hunter Travis in 1978. Jack's mother was pregnant with him at the time, and put him up for adoption, where Jack got "lost in the system" and Travis was unable to find him, though he admits to being somewhat unwilling, as Jack was only a child and had no idea about his true nature. In late September 2008, Jack begins noticing that he's changing: he has an insatiable hunger, which drives him to eat even raw meat; his bones are moving beneath his skin, he has difficulty controlling himself and he suddenly demonstrates superhuman strength.
Sam and Dean confront him when they noticed that he started to eat raw meat, once they have been alerted to the possibility of his transformation by Travis, but Jack sends them off his property when they tell him they'll have to kill him if he eats human flesh and changes completely. After, Jack stays away from his home, fearful of his urges and appetites.
He finally returns to find his wife Michelle held hostage by Travis, who also overpowers Jack and ties him up. Jack tries to reason with Travis, finally asking him to kill him but let Michelle go, saying that "she's not part of it." Travis forces her to reveal that she is pregnant. When Travis begins pouring gasoline on the floor, intent on killing them both so that Michelle's child will not become another rugaru, Jack breaks free and attacks him, taking a bite from his neck and completing his outward transformation. He releases Michelle, who is terrified by his behavior and escapes.
Jack eats Travis, and knocks out both Sam and Dean when they arrive to check in on him, locking Sam in a closet. Sam tries to convince him that his actions are more important than his nature, but Jack is overwhelmed with despair and hunger, and is fighting not to eat Dean, who is still unconscious. Before he can, Sam picks the lock, breaks out and sets up his flamethrower. Jack turns his attention away from Dean and willingly allows Sam to set him on fire, killing him.