Rover is a street dog that lives a life of fun in Las Vegas with his owner Connie, a showgirl. He gambles and chases girls with his best friend Eddie. One night, he sees Connie's boyfriend, Rocky, in a transaction with a pair of gangsters, and accidentally disrupts it. Thinking that Rocky is an undercover cop setting them up, the gangsters flee, telling Rocky that he has blown his last chance. The next day, Connie goes on the road for two weeks, leaving Rocky to look after Rover. In retaliation for ruining his deal, Rocky stuffs Rover in a bag, drives him to Hoover Dam and throws him into the water. The bag is later pulled out of the water by two passing fishermen, who take Rover back to shore and place him in the back of their pickup truck. However, Rover regains consciousness and jumps out of the truck when the fishermen stop for gas, and begins to wander down the road. He ends up in the countryside, and eventually runs into a farmer, Cal, and his son, Danny, who convinces his father to take the dog in. Cal agrees on one condition: at the first sign of trouble, he'll be sent to an animal shelter, and if nobody claims him, the animal shelter can put him down.
Rover has difficulty adjusting to life on the farm, but with the help of Daisy, a beautiful dog next door, and the other dogs on the farm, he succeeds in earning his keep. Rover spends Christmas with the family, and begins to fall in love with Daisy, who returns his affections. However, one night, a pack of wolves attempt to kill a turkey on the farm. As Rover tries to save the turkey, the wolves ran off, but the bird ends up dead and Cal mistakenly believes Rover to have been responsible. The next morning, Cal takes Rover into the woods is about to put him down, but is attacked by the wolves. Rover manages to fight the wolves off, and brings the other farm dogs to get the injured Cal home.
Rover's heroics make the papers, allowing Eddie and Connie to find out where he is. Danny informs Rover of his trip back to Las Vegas and he departs the farm. Although initially happy to be reunited with Connie and his friends, Rover soon begins to miss his life on the farm. When Rocky comes into Connie's dressing room, and upon seeing him, Rover initiates revenge for what he did to him. After Rocky accidentally confesses to what he did, Connie angrily breaks up with him. Infuriated, Rocky tries to retaliate against Connie, but Rover and his dog friends chase him out of the casino, where he runs into a limo filled with the gangsters. At first, Rocky is relieved that they seemingly came to his rescue but then questions why they were even there in the first place. The thugs proceed to reveal that they set him up and imply that they are going to murder him by throwing him over the Hoover Dam, much to Rover's delight as he watches the limo drive off with a horrified Rocky.
Sometime later, Rover, missing Daisy, becomes depressed. Connie, realizing her old companion met someone, takes Rover back to the farm to stay. Rover is reunited with Daisy, who reveals to him that he is now a father, unveiling six puppies. The story ends with Rover teaching his kids how to play cards, and playfully chasing Daisy around the farmyard.