Linda has the bright idea to celebrate Hattie's 75th birthday by throwing her a surprise party. Floyd tries to warn Linda against this idea because he feels it would be too dangerous, but she goes forward with the party despite Floyd's objection.
The decorations and guests are all in place when Hattie walks through her front door and they surprise her—but she surprises everyone else when, startled, she instinctively pulls her handgun and shoots three rounds into the living room. Fortunately, no one gets hurt. Later, Hattie explains the necessity of having her pistol when Marianna objects to guns in general.
Hattie slips and falls while working late at the diner. Linda insists that Hattie go to the hospital, but Hattie refuses. Later, while Hattie is being cared for by family and friends, she begins to drive them crazy by constantly asking them to wait on her hand and foot.
Later that night when they check in on Hattie at her home, everyone is shocked when they see her bouncing down the stairs with ease. After Hattie's scheme is revealed, she falls and hurts herself for real. This time, no one will believe her!
Marianna gets Drew involved with volunteering to help mentor young mothers from a local shelter. After a luncheon at the Love Train Diner with the young mothers, Hattie discovers a baby in the bathroom. Floyd, Hattie and Linda frantically try to find the baby's mother. All ends well, though, when they find out it was all a big misunderstanding.
It's time for Hattie's annual physical, and she doesn't want to go. Linda threatens to call the IRS if she doesn't, though, which prompts Hattie to have a change of heart.
After returning from her doctor's appointment, Hattie overhears Vivian telling everyone about her horse, Old Girl, having to be put down because she has cancer—and Hattie thinks they're talking about her! Believing she's at death's door, Hattie suddenly (and shockingly) adopts nicer, kinder attitude toward her family and friends. Moved by their matriarch's good behavior, her family decides not to tell Hattie the truth until she lays out her last will and testament.
Sam has a verbal altercation with a beautiful woman at the Love Train Diner after she turns down his advances. Then, Danny and Sam arrive late for work and find that the woman from the diner is their new boss, Marianna. As fate would have it, Drew also knows Marianna: They were roommates freshman year in college, and Drew has disliked her ever since. After discovering that Drew withheld information about the new boss starting, Danny and Sam get even by telling Marianna that Drew is looking for a new roommate. Unable to say no, Drew reluctantly invites Marianna to move in.
It seems that Sam is holding up his end of the bargain and has stopped throwing wild parties. However, things take a turn for the worse when he confesses that there is a dead woman in his bedroom. When Danny and Drew go in to check on her, they discover her medical alert bracelet. Once she's revived, Danny and Drew get the woman to sneak out and lead Sam to believe that she really is dead, all in an effort to get Sam to stop his philandering.