Dean Winchester was born on January 24, 1979. He loves his car (a black four-door 1967 Chevrolet Impala), his family, and classic rock music. He always wears a brass amulet on a long black cloth band necklace. While the significance of the necklace is unknown, it is clearly quite important to Dean (Ackles has claimed in an interview that it is an Egyptian protection amulet, but this has been yet to be proved in an episode).
From an early age, he was trained by his father to hunt demons. He took to the job, thus he has several notable advantages for a human: He's an exceptional shot, has knowledge beyond the norm about the supernatural, is a skilled fighter, and appears to have some proficiency with melee weapons. He is the only one allowed to call his brother by Sammy.
When Dean was four years old, his mother Mary was killed in his younger brother Sam's bedroom. Twenty-two years later, The Demon responsible for their mother's death kills Sam's girlfriend, Jessica Moore. Together, Dean and Sam go on a road trip to fend off supernatural creatures and search for their father, John, who occasionally leaves new missions for them to complete.
Early in the season ("Skin"), Dean and Sam battle a shapeshifter responsible for a string of brutal murders in the St. Louis, MO area. During the course of the episode, the shapeshifter assumes Dean's form, causing police to believe that Dean is responsible for the murders. However, Dean kills the shapeshifter while it is still in his form, and the authorities officially declare him dead.
The season finale concluded with Sam, Dean, and John escaping from a clash with "The Demon" in Salvation, Iowa. While Sam was driving to a hospital after Dean and John were injured, a demonically possessed driver drove his truck into the Impala, causing massive damage to the car and the Winchesters inside.
All three of the Winchesters survive the wreck, although Dean is more severely injured than his father and brother. In the first episode of Season 2 ("In My Time of Dying"), Dean is in a coma and a reaper, Tessa, tries to convince him to die. In order to save him, John makes a deal with The Demon, trading his life for Dean's. Before he dies, John whispers something in Dean's ear which the audience cannot hear.
Throughout the first half of the second season, Dean struggles with the death of his father, as well as with the knowledge that he was the one who was supposed to have died. Furthermore, he is haunted by his father's last words to him, and at the midpoint of the season, it is revealed that John told Dean that The Demon intends to turn Sam to evil, and if Dean can not save Sam, he must kill him.
During an investigation in Baltimore, MD ("The Usual Suspects"), Dean is arrested in connection with another series of murders. It is revealed that Dean has a rather impressive police record, with charges over the years including credit card fraud, breaking and entering, and grave desecration. Although Sam and Dean are able to prove that the murders were actually committed by one of the detectives on the case, it is unclear whether or not the charges against Dean were ever officially dropped. However, the problem still remains that the authorities have realized that Dean is not dead, as they had previously believed. A team of FBI agents, led by Special Agent Victor Hendrickson catches up with Dean and Sam in Milwaukee, WI ("Nightshifter"), where attempted bank robbery and several more murders are added to Dean's list of supposed crimes.
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