Grace is a cow owned by Pearl, and she resides on Pearl's farm Little Patch of Heaven. Unlike Maggie and Mrs. Calloway, Grace tends to be more of a follower than a leader. She is very sweet, optimistic, and happy-go-lucky cow, and sometimes plays peacemaker between her two headstrong friends. Grace is one of the only cows who is completely immune to the hypnotic yodeling of Alameda Slim; this immunity is apparently due to Grace's complete tone-deafness. However, Grace appears to have no clue that she is tone-deaf; she loves to sing (and is usually off-key) and considers herself to have perfect pitch.
Residing on Pearl's farm, Little Patch of Heaven, Grace is one of two cows, the other being Mrs. Calloway. Though more of a follower, Grace has recently been encouraged to take more responsibility in leading the farm. However, the idyllic existence is interrupted when Maggie, a headstrong show cow, arrives at the ranch, and begins clashing with Mrs. Calloway.
When it is revealed that Little Patch of Heaven may be auctioned off in three days due to debt problems, Grace and Mrs. Calloway are convinced by Maggie to travel with her to the town fair, in hopes of winning prize money to save the farm. Along the way, Grace learns of Maggie's past; she was the only cow left after Alameda Slim came and mysteriously stole the other cattle on her previous ranch home.
Upon arriving in town, they accidentally go to a saloon when they get scared by sounds, mistaking them for a gunfight, and make a huge mess there. After being kicked out, they meet Buck, Sheriff Sam Brown's horse, and Grace and the others learn that a reward is being offered for the capture of Alameda Slim, which would provide enough money to save the farm, and tries convincing her fellow cows to help her, but Mrs. Calloway disagrees. She then gets in a fight with Maggie after the latter knocks Mrs. Calloway's hat off, which lands in the mud. Sheriff Sam Brown soon breaks up the fight by tying all three bovines up to a wagon that went to a ranch. On the way there, the cows pass by Maggie's old home, which has been auctioned off to a Mr. Yancy O'Del. Mrs. Calloway and Grace learn that Alameda Slim, a notorious cattle wrestler, stole all of the cattle, and Maggie was only spared because she had been locked in the barn after winning a show.
The three cows hide at the ranch filled with longhorn steers in an attempt to catch Slim. However, they soon discover how Slim is able to steal the cows: his yodeling puts the cows into a trance and follow him. Both Mrs. Calloway and Maggie are entranced, but Grace is unaffected, due to being tone deaf, and pulls the wagon to awaken the other two. When Buck decides to capture Slim himself, the cows follow his trail in an attempt to pass him, but lose the trail in a downpour. This leads to a fallout between Maggie and Mrs. Calloway, who accuses Maggie of dragging her and Grace along for a personal vendetta. Grace and the others learn that a reward is being offered for the capture of Alameda Slim, enough to pay off the farm debt. Thus, Grace and the others decide to bring Alameda Slim in to college the reward. That night, the three cows hide in a ranch with other steers. Alameda Slim suddenly appears, revealing an ability to hypnotize cows by yodeling, including Maggie and Mrs. Calloway. Luckily, Grace is completely tone-deaf and thus unaffected. After a struggle, she is finally able to break the spell and bring Maggie and Mrs. Calloway back to their senses, though Alameda Slim escapes.
The next morning, Grace and the cows meet Lucky Jack, a jackrabbit who lost a foot to a lucky charm. After learning that Lucky Jack lost his former home, an old mine, to Alameda Slim, the cows ask the rabbit to take them to it. The cows form a plan to capture Slim. At Grace's suggestion, Mrs. Calloway and Maggie don earplugs so that Slim's yodeling does not affect them. The cows are able to capture Slim, and flee on a steam train, with Slim's accomplices and buyer in close pursuit. However, Slim is freed by Rico, a fake bounty hunter who secretly works for Slim. Alameda Slim dons his alter ego, Mr. Yancy O'del, and plans on attending the auction of Patch of Heaven. However, Grace and the others use the train to follow him and are able to expose Slim's identity to the Sheriff and Pearl, who are both shocked that the auctioneer who is buying the farm is Alameda Slim, resulting in his arrest and the farm being saved by the prize money.
When Grace and Mrs. Calloway thought Maggie left the farm for good, they start to miss her and begin saying nice things about her. However, it is revealed that Maggie did not leave and decided to stay in Patch of Heaven after she heard Grace and Mrs. Calloway say nice things about her. Grace is last seen dancing with all the other farm animals in celebration of Little Patch of Heaven being salvaged and re-opened.