Dean Winchester was transported back to Lawrence, Kansas, 1973 by Castiel, with only the cryptic assignment: "You have to stop it." Posing as hunter 'Dean Van Halen', he met his mother Mary and was amazed to find out that she was a hunter, and so were her parents. Her father, Samuel Campbell, made it clear that did not trust other hunters or want them in his house. Even so, Dean managed to get close enough to find out that they were working a job on the Whitshire farm. The name sounded familiar to Dean; Samuel said that was because it had been in the papers--Tom Whitshire had died from getting tangled in a combine that he shouldn't've even been trying to operate because his crops were already dead. They were waiting for evidence of any demonic omens, like electrical storms, to arrive in the mail. Dean suggested they team up to expedite the case, but Samuel reiterated that they worked alone.
When Samuel and Mary arrived at the Whitshire place the next day, Samuel, posing as a priest, was annoyed to find Dean already there, also posing as a priest. Dean left him in an awkward stance with Mrs. Whitshire, and joined Mary in questioning her son.
Charlie, guilt-ridden, told Dean and Mary that he'd discussed his abusive father with a stranger, believing him to be just a run of the mill "Bible-thumper." He told him that he "wanted the beatings to stop" and the next thing he knew, his father was dead. Dean pressed him to say whether the stranger asked for anything in return; he admitted said that stranger said he'd visit Charlie in ten years and that maybe he'd want something from him then. He described him as a normal looking guy, except for his eyes. Dean asked were they black or red? He replied that he could have sworn that when the light hit them, they were pale yellow. Hearing this, Dean surmised, incorrectly it turned out, that the Yellow-eyed Demon was the "it" that Castiel had sent him back to stop.
Dean consulted his father's journal and found an entry about the deceased: TOM WHITSHIRE. 1973 LAWRENCE, KANSAS. DEATH BY THRESHING.