Danny withholds his half of the rent until Sam agrees to rein in his wild lifestyle. Sam thinks Danny is completely overreacting. Danny then gives Sam an ultimatum about his partying, which causes Sam to verbally evict Danny from their apartment. In the end, however, Sam comes to realize he needs to work on a compromise with Danny in order to keep the peace—and Danny's half of the rent.
As Linda and Marty prepare to attend the Mayor's Ball, Danny feels the need to protect his mother, so he solicits Floyd's help to check out Linda's new man. In an attempt to interrogate Marty, they end up scaring him off. Linda then lovingly reassures Danny that her past bad relationships have made her stronger and that he doesn't need to be so protective of her. Ultimately, Marty returns for Linda and tries to start over with Danny.
Marty invites Linda to his annual office costume party. This year the theme is the Roaring Twenties, and Linda agrees to go. During her preparation for the party, however, Hattie misinterprets a conversation that she has with Linda about celibacy, which in turn leads Hattie to mislead Danny into thinking that Linda has turned to a life of prostitution.
Later, Danny's nightmare seems to be further realized when he sees Linda and Marty in their costumes—Linda as a flapper, and Marty as a pimp. Danny tries to defend his mother's honor by not allowing her to go out with Marty. Linda finally sets the record straight when she tells everyone that she has not turned to prostitution, but rather that she has decided to live a life of celibacy.
A frustrated Danny has grown tired of Sam's incessant partying. Danny vents to his grandmother, Hattie, and mentions that he may need to move back in with her. Upon hearing that news, she decides to take matters into her own hands to keep her grandson out of her house.
Hattie shows up at one of Sam's parties and gives him a drink called white lightning. Although he is warned by Floyd not to partake of Hattie's homemade liquor, Sam ignores the warning and drinks it anyway.
Sam wakes up the next morning handcuffed to Hattie, spending the rest of the day thinking he's had sex with her. Horrified, Sam vows to stop partying and drinking so much.
After Vivian's restaurant burns down and goes out of business, the Love Train Diner opens its doors to more customers. Unfortunately, they are less than satisfied with Hattie's cuisine, and business suffers.
With the diner being financially strapped, Hattie finally accepts Vivian's offer to form a partnership that will increase their revenue. Elsewhere, Danny, Sam and Drew vie for a promotion at work. When none of them get the job, they prepare for the arrival of a new boss.
Floyd and Hattie's business suffers after Vivian puts up a billboard slamming the Love Train Diner for being closed by the Board of Health. Hattie gets her revenge, though, by spray-painting vulgarities on Vivian's billboard.
When Vivian confronts Hattie about destroying her property, an argument ensues, and the entire restaurant overhears Hattie warn Vivian to be careful that her restaurant doesn't burn down.
Unfortunately for Hattie, a suspicious fire erupts at Vivian's Diner, and it burns to the ground on that same night. After being accused by everyone—including her own family—Hattie is vindicated when the fire marshal determines that it was not arson but negligence on Vivian's part that caused the blaze.