The life and training of a Hunter is difficult and rigorous...and John Winchester is starting at the beginning! As he takes the first step on this harrowing journey, he must make a difficult and gut-wrenching decision in regards to his children. And it's time John was truly initiated into the Hunters — with a trip to Harvelle's Roadhouse Bar!
This issue begins in 1991 and flashes back to 1982 when Dean is only about 4 years old and Sammy is just around 1 year old.
In Issue #3 John is taken to Harvelle's Roadhouse, the bar owned by Ellen and Bill Harvelle which is a popular hangout for demon hunters. Ellen offers to watch the boys while Hunter, John, and local named Ichi go out looking for what they believe to be a "Heeler" - that's a tall man in cape that can superjump. It turns out they are really on the trail of a shapeshifter.
This is a pivotal point where eldest son Dean witnesses his father killing someone for the first time. Dean doesn't know that it's a shapeshifter and only sees his father killing Ichi when the demon killed the really Ichi back in the woods. It's a major event for John who did not want to resort to killing anything except the demon that killed his wife. For Dean, he sees his father in a dangerous way and tells Sammy that he's leaving hoping that if John realizes Sammy doesn't have an older brother to take care of him, he'll actually become a real father to him.