After another Sunday with the Simpsons, Grampa meets Beatrice "Bea" Simmons, a resident at the Springfield Retirement Castle. They go on a date and fall in love. When Bea's birthday arrives on a Sunday, Homer makes Grampa come on a family outing to the Discount Lion Safari, because he thinks Grampa is making up that he has a girlfriend. The outing causes Grampa to miss Bea's birthday. At the safari, the family's car becomes stuck and the lions begin circling it, trapping the family overnight. After the workers help chase the lions away, Grampa returns home expecting to see Bea. However, Homer pulls up just in time for the ambulance to pull away. Jasper tells Grampa that Bea died of a burst ventricle (Grampa comments that they may say Bea died of a burst ventricle, he knows she "died of a broken heart", both symbolically and literally). while Grampa was out with the family. Left deeply depressed by her death, Grampa attends her funeral, where he angrily lashes out at Homer and refuses to speak to him, as he blames Homer for preventing him from attending Bea's birthday party and being with Bea in her final moments and swears never to forgive Homer, leaving Homer miserable.
Grampa receives Bea's inheritance of $106,000 from Lionel Hutz. First, he looks at buying things for himself, but doing so brings him no joy. While on a roller coaster, Bea's ghost appears and suggests that he should spend the money with other people, and also tells him to forgive Homer because deep down Grampa still loves him. After interviews with many people across Springfield (including Mr. Burns, ironic, given his obvious wealth) who only want to spend Grampa's money on things for themselves, Lisa suggests that he should give the money to worthy causes. Feeling he does not have enough money to help as many in need of help as he can, Grampa attempts to double his money by gambling at a casino but Homer stops him—and just in time, since Grampa would have lost the entire inheritance at the roulette wheel. Grampa forgives Homer, and decides to spend the rest of the inheritance on improving the retirement home and adding a new hall named after Bea.