Virginia City-area farmers become worried when a salt shortage results in mass deaths of cattle. Ada Halle has inherited her father's mine, and with the help of her fiancee town sheriff Vern Schaler, tries to come up with a reasonable method of distributing the salt.
The two decide that, because of the shortage, they'll have to make do with 60 percent of the salt they received last year at the same price they paid in previous years. Though disappointed, the farmers agree to the price.
But, of course, one rancher objects. That rancher is Cash Talbot, a shrewd, wealthy businessman who argues the salt should be distributed per demand; those with smaller herds get less salt, and because he has a bigger herd this year, he should get more.
The Cartwrights, along with Candy, find out that Talbot's herd, in fact, is smaller than last year. They accurately surmise Talbot wants to drive the price of salt out in order to eliminate competition. Knowing the situation is a race against time and his patience, Talbot and his foremen also hope to turn normally allied ranchers against one another. One of the ranchers tries standing up to Talbot, but is wounded.
Ada calls a meeting of the anxious ranchers, setting the price at $1 per head of cattle each farmer owns – a price that is out of the reach of some farmers. Talbot unsuccessfully tries to convince Ben to accept Ada's offer. Ben, instead, argues that if he and Talbot were to refuse Ada's offer, since they are the only two ranchers that are wealthy enough that, if their cattle herds were wiped out, they could withstand the losses. They can force a lower asking price that the smaller ranchers can afford. The bullheaded Talbot refuses to yield, citing the "dog-eat-dog" world of ranching.
Later, with his patience running short, Talbot agrees to Ada's offer, plus $5,000 if he were to get every block she has in her supply. He then declares his refusal to share the salt with other farmers. A shocked Ada realizes that, by selling to Talbot, he would drive the other ranchers out of business and he'd own the only herd in the region. Talbot would also control the price of beef, not to mention the price of cattle. Talbot knows this, and offers to share some of his profits with Ada.
Ben stops by the salt stockyard to make an offer of his own, so that the Ponderosa and the other ranchers can have the salt. Too late, he later realizes. A disgusted Ben steps outside to ponder strategy, but then a deputy warns him that Talbot made the pricey offer. Ben stops Ada from writing up the receipt, declaring a $5,001 offer by a newly formed cooperative of ranchers (financed by the Cartwrights).
Vern stops by and overhears part of the commotion; while Vern sympathizes with the ranchers' plight, he notes the law sides with Talbot, who made a free-and-clear offer. Ben warns Vern he'd be endorsing mass murder of cattle herds if Talbot were allowed to get away with his scheme. Vern agrees and, after declaring the sale null and void, kicks Talbot and his cronies out of town.
Vern, who advises Ben to get over to the stock house before Talbot gets there, has a private moment with Ada. He breaks off the relationship, saying he never considered Ada to be greedy or selfish, but the whole situation with the salt made him see otherwise. Ada begs for forgiveness, saying money never meant anything to her, but Vern needs to get to the stock house himself to provide security.
Ben arrives at the stockhouse to find the deputy dead and Talbot and his henchmen waiting. At gunpoint, Talbot wants Ben to individually call the ranchers into the barn so he can kill them. Ben warns Talbot that the odds will catch up with him, but that doesn't really concern Talbot.
But it should. The Cartwrights and Vern realize Ben is in trouble, and while Candy, Little Joe and Hoss take control of the henchmen, Vern and Talbot shoot and kill each other in a gunfight. Ada arrives and finds Vern's lifeless body. Realizing she lost the only thing that ever truly mattered to her, a grieving Ada calls off the $1 per head price and allows the salt to be sold at a fair price.
In a show of grace, Ben and his fellow ranchers give Ada a cash gift tucked inside an envelope, marked "from the friends of Vern Schaler."