Plot
In the American West in 1851, gunfighters Eli and Charlie Sisters are hired by the wealthy "Commodore" to kill a man named Hermann Warm.
John Morris, a private detective, has been hired by the Commodore to track Warm down, and hand him over to the Sisters brothers. Morris finds Warm traveling by wagon train to California with the Gold Rush and befriends him. They travel to Jacksonville where Morris has arranged his rendezvous with the Sisters brothers. Warm finds Morris' handcuffs, realizes his true intentions, and threatens him at gunpoint but Morris overpowers him. Warm reveals that he plans to find gold using a chemical formula of his own invention; the Sisters brothers have been sent to retrieve the formula, most likely by torturing Warm before killing him. Refusing to allow an innocent man's murder, Morris frees Warm and the two leave Jacksonville. On the road toward San Francisco, Warm reveals that his ultimate plan is to create a utopian society in Dallas, Texas.
The brothers' pursuit is plagued by misfortune. A grizzly bear attacks their camp and mauls Eli's horse, Eli becomes very ill from swallowing a spider in his sleep and Charlie is repeatedly drunk and too hung over to ride. When they discover Morris' betrayal in Jacksonville, they follow the pair to the town of Mayfield. At Ms. Mayfield's hotel and brothel, she denies having seen Warm and Morris but offers the brothers a warm welcome. A sympathetic prostitute warns Eli of an impending attack and he attempts to leave with a drunken Charlie but they are cornered by Mayfield's gunslingers. The brothers kill the gunslingers and interrogate Mayfield as to Warm's and Morris’ whereabouts, before murdering and robbing her.
In San Francisco, Charlie and Eli argue about continuing their hunt. Eli wishes to retire and open a store, but Charlie angrily rejects this idea. The next day, Charlie reveals that he has found a claim staked in Morris' name a few days' ride away. Eli agrees to complete the hunt as their final job.
On the way to the claim site, the brothers are ambushed and captured by Warm and Morris, who are then attacked by Mayfield's men sent before her death to claim the formula for herself. The four team up to kill Mayfield's men, after which Charlie and Eli agree to help Warm and Morris find gold in exchange for half the takings. Morris is revealed to be a wealthy young man from Washington DC, who came west in rebellion against his father, now dead, and to whom Warm's Dallas phalanstère project has at last given a purpose in life. Working to dam the river, the new partners develop a camaraderie. Eli reveals to Warm that Charlie killed their abusive, alcoholic father when they were young, and that Charlie's short temper and violent tendencies put him in danger, so Eli reluctantly took up their present employment to protect him.
The dam is completed and Warm explains that when his chemical formula is added to water, it causes gold ore to glow briefly, but is extremely caustic. The men pour the formula into the river and begin gathering the gold. When the glow begins to fade, Charlie panics and tries to add more formula, but spills the undiluted substance onto his hand and into the river. Morris, rushing to restrain Charlie, stumbles and is submerged in the contaminated water while Warm, ignoring Eli's warnings, jumps in to rescue him. The next day, Warm, blinded and badly burned, dies from his injuries while Morris shoots himself to end his suffering.
Eli takes Charlie to the nearest town, where a doctor amputates his arm. Hired guns sent by the Commodore arrive and demand their surrender. Eli shoots them and the brothers spend many days fighting against various hired guns until he and Charlie decide they must kill the Commodore. They arrive in Oregon City to find that he has already died. The brothers are the only mourners at the Commodore's open casket; Eli punches the corpse several times "just to make sure". The brothers return home to their mother; though initially suspicious, she welcomes them in.
