Plot

After John's mentor, a vampire hunter, is murdered, John shows up to help his sons solve the case. The vampires have taken an antique gun with supernatural powers. The Winchesters set out to retrieve the gun.

After Daniel Elkins, a vampire hunter and John's mentor, is murdered, Sam and Dean are surprised when John himself shows up to solve the case. John discovers the vampires have taken an antique gun, which has the power to kill all supernatural beings. The Winchester family sets out to retrieve the gun from the vampires so they can use it to kill the demon that took Sam and Dean's mother.—Anonymous

While investigating the death of an old man called Daniel Elkins in Manning, Colorado, Dean and Sam meet their father. John Winchester explains to them that Elkins was his friend and he had a Colt capable of killing any supernatural creature. They disclose that the old man was killed by vampires, and together, the Winchesters chase the evil night creatures.—Claudio Carvalho, Rio de Janeiro, Brazil

Dead Man's Blood opens in a roadside bar in Manning, Colorado, where Daniel Elkins [Terence Kelly] sits drinking shots and making notes in his journal, which looks a lot like the journal kept by John Winchester. When three guys and a woman enter the bar, Elkins immediately gathers up his notes and rushes home. He locks the front door behind him, but it opens anyway and the woman (a vampire named Kate) steps in. Elkins tosses a knife into her chest, but she calmly pulls it out. Elkins tries to barricade himself in another room. As Kate [Anne Openshaw] knocks down the barricade, Elkins takes an antique gun from his safe and loads it. The barricade breaks down and Kate comes in just as two more vampires crash through a window. Kate laughs when she sees the gun. She picks it up as the other vampires feed on Elkins.

Dean and Sam are having a bite to eat in a cafe. While Dean reads the newspaper, Sam is surfing on his laptop, looking for news reports which may indicate supernatural activity. The only thing worthy of mention is a Colorado man who was found mauled in his home. Police can't tell if it was a bear attack or a robbery; could it be a supernatural attack? When Sam mentions the man's name...Daniel Elkins...Dean thinks it sounds familiar and consults his Dad's journal. Sure enough, Daniel Elkins is in there, so the boys head for Colorado. First stop is Elkins' cabin. Other than a mess, they find only two things that might suggest supernatural activity--a ring of salt inside the front door and Elkins' journal. Then Dean notices some scratches carved into the wood floor and makes a rubbing, which reveals the location and combination of a post office box. They immediately drive to the post office, find the box, and open it. Inside is a letter addressed to "J.W.". Could J.W. be their father, John Winchester? They return to their car and ponder over whether or not to open the letter.

Suddenly, there is a knock on the car window. It's their father! He read the news about Elkins' death and came right away. Elkins was a vampire hunter as well as John's good friend, although they haven't seen each other in years. John opens the letter and begins to read aloud. "If you're reading this, I'm already dead..." He stops reading to ask his sons whether they noticed an antique Colt revolver when they searched Elkins' cabin. Dean remembers seeing the case, but it was empty. John explains that Elkins was killed by vampires and that they must get back the gun. It's not an ordinary gun, he explains. It was made by Samuel Colt in 1835 for a vampire hunter, and legend says that the gun can kill anything. John thinks it may be the means by which to destroy the demon who killed his wife.

Meanwhile, the vampires are also hunting. One of them has laid himself across the road. When a young couple almost hits him with their car, they stop to help. When John hears a call over his police radio of a 911 call reporting a body in the road but no one there by the time the police arrived, he immediately recognizes it as the work of vampires. John and sons follow the call to the accident site where John finds a vampire tooth, confirming his suspicion. It looks like the vampires are heading west, so the Winchesters follow, hoping to find the nest. The vampires are holed up in what looks like an old barn. They have tied up the couple and are taunting them while they wait for their lead vampire Luther to return. Luther and Kate are mates and, when he returns, she presents him with the antique Colt revolver. Luther recognizes it.

The next morning, the Winchesters have located the nest. Armed with machetes, they quietly enter. The vampires are there, sleeping in hammocks. While John searches for the gun, Sam tries to release the girl who made the 911 call (the vampires have already killed her boyfriend), but she was fed Kate's blood during the night and is now united with the vampires. She screams, which wakes up the vampires, and the Winchesters have to run for their lives, leaving the gun behind. Plan 2 calls for Dean to break into a funeral home and obtain some blood from a dead man's body. Later that night, they set up a ruse. Dean fakes car trouble on the road near the vampires' nest. When vampires Kate and Hank stop to offer help, John and Sam shoot them with darts that have been dipped in the dead man's blood, which acts like poison on the vampires, causing a type of "blood sickness." Kate passes out, and John beheads Hank. When Luther learns that the Winchesters have taken Kate, he goes hunting for them.

While John (with a weakened Kate in his truck) cruises along the highway waiting for Luther to catch up with him, Dean and Sam invade the nest, behead a few vamps, and release their human captives. Back on the highway, Luther has caught up with John. John offers a trade, Kate for the Colt. Luther agrees and places the gun in the road. When John, still holding a knife to Kate's neck, bends down to pick up the gun, the vampires attack him. Just as it looks like John is a goner, Sam and Dean step out of the bushes and fire dead man's blood-tipped darts at the vampires. Dean picks up a machete and turns to Luther, but Luther grabs Sam and threatens to break his neck unless Dean drops the machete.

"Why can't you people leave us alone?" Luther scowls. "We have just as much right to live as you do."

"I don't think so," says John, as he fires a bullet from the Colt revolver that goes right through Luther's forehead, destroying Luther right in front of Kate's eyes. Kate escapes.

Epilogue: Back in their motel room, the Winchesters discuss the fact that Dean and Sam saved John's life, showing that they are stronger together than apart. The three of them decide to hunt together from now on. [Synopsis by bj_kuehl]