Bobby Singer

Background
Bobby is a hunter and an old friend of John's. He owns Singer Salvage Yard. He's been  gathering from the wealth of books in his house and his dialogue and role in "Devil's Trap", is somewhat of a demonology expert.

Season 1
With John held captive by the demons, the boys turn to Bobby for help. He gives Sam the Key of Solomon. When Meg turns up at his house, they restrain her using a devil's trap (symbol) painted on the ceiling. It is Bobby who alerts the boys to the fact that Meg is not a demon herself, but a woman possessed by one. After the demon is exorcised, and Meg dies, Bobby agrees to dispose of her body and the authorities.

Season 2
With Dean in a coma and John injured, Sam goes to visit Bobby who has towed the Impala from the crash site. Sam has to retrieve the Colt, and John has given Sam a list of herbs to get from Bobby. Sam is distressed at the wrecked state of the Impala, and Bobby suggests scraping the car, until he sees that to Sam it embodies the state Dean is in, and to give up on the Impala would be to give up on Dean. He also informs Sam that the items Sam has requested are not for repelling a demon, but for summoning one.

Although Bobby is not present in this episode, Sam and Dean are staying with him as they recover from their wounds, and the death of their father. Dean uses Bobby's tools to repair the Impala. They have been there a week at the beginning of the episode. Bobby lends them a van (which makes Dean feel like a "soccer mom") when they drive to meet Ellen at the Roadhouse.

When Sam is possessed by the Meg!Demon, he turns up at Bobby's place, intending to kill him. However Bobby is alerted to the demon's presence when it reacts to holy water he has spiked Sam's beer with. Again, the demon is restrained under the devil's trap (symbol), but this time the exorcism Dean attempts fails because the demon has bound itself to Sam's body with a brand. The demon is expelled when Bobby burns across the brand with a hot poker.

Bobby is aware Sam killed another hunter, Wandell, while possessed, and advises the boys to leave before other hunter's find them. He gives them each a charm to ward off possession. When Sam disappears, Dean turns to Bobby for help. Together they search for Sam, and find the burnt out ruins of the Roadhouse. After Dean receives the vision of Sam's location, it is Bobby who deciphers that the town is Cold Oak. When they arrive there, Bobby pursues Jake after he stabs Sam, but loses him in the woods.

Bobby tries to look after Dean in the wake of Sam's death, but Dean pushes him away in anger. Bobby responds with understanding, and leaves. When Dean and Sam turn up at Bobby's, he immediately knows Dean has made some deal to resurrect Sam. Out in the middle of his junkyard he confronts Dean, and is upset when he learns Dean only has a year to live. His affection for Dean is clear, when he despairs that Dean doesn't value his own life. When Ellen appears, having escaped the demon attack on the Roadhouse, Bobby makes her drink a shot of holy water to ensure she is not possessed.

Bobby is part of the effort to stop the opening of the Devil's Gate in Wyoming, and it is he and Ellen who actually close it.

Season 3
Bobby tracks down a possible omen in Nebraska, and the boys join him to investigate. They meet Tamara and Isaac, a married hunter couple Bobby knows. While Bobby urges caution, they are attacked by demons and Isaac is killed. Bobby works out that the demons are the Seven Deadly Sins, and with Sam, Dean and Tamara and the intervention of a mysterious girl, the demons are trapped and Bobby exorcises them.

At the beginning of the episode, Sam is on the phone to Bobby as they try to translate an ancient document.

After finding John's lock-up has been broken into, the boys contact Bobby, who confirms that he built the Curse Boxes, one of which has been stolen. Later, he explains the curse of the Rabbit's Foot and starts researching how to destroy it. During this conversation, he appears to be working on the Colt. After Bela steals the Rabbit's Foot, Bobby identifies her to Dean, and tracks down her address for him. Finally, Bobby provides Sam and Dean with a ritual which destroys the Rabbit's Foot and breaks its curse.

Bobby is working on the Colt, with Dean's help. After the boys leave for Ohio, he is test firing the Colt, when Ruby appears, and offers to help turn it back into a demon-killing weapon. Summoned by Sam he arrives to help, only to be struck down by Father Gil. At the end of the episode he reassures Dean that Sam is okay - that nothing has changed since he came back from the dead.

Months later, Bobby was investigating a Doctor who had been studying sleeping habits, but testing people with nightmarish serum-induced dreams. Bobby fell under what Sam described as a Freddy Krueger type dream state, and Bobby went into a coma.

Season 4
Bobby was the first person to see Dean Winchester alive, after he was brought back to life.

Appearances

 * "Devil's Trap"
 * "In My Time of Dying"
 * "Born Under a Bad Sign"
 * "Tall Tales"
 * "All Hell Breaks Loose - Part 1"
 * "All Hell Breaks Loose - Part 2"
 * "The Magnificent Seven"
 * "Bad Day at Black Rock"
 * "Sin City"
 * "Dream a Little Dream of Me"
 * "Mystery Spot"
 * "Time Is on My Side"
 * "No Rest for the Wicked"
 * "Lazarus Rising"
 * "Are You There God? It's Me, Dean Winchester"

Trivia

 * Bobby lives in South Dakota
 * Owns a blue Ford tow-truck with Lawrence County, South Dakota plates : 9NO3L1. This is probably a reference to Jim Beaver's role in the HBO Western drama Deadwood. Deadwood is the county seat of Lawrence County. In Season Three he also drives a 1971 Chevelle.
 * His dog, who has only appeared in one episode, is called Rumsfeld.