Homer is diagnosed with narcolepsy — but instead of returning home with his prescription medication — he returns home drunk. He and Marge visit a marriage counselor and have a trial separation, during which Homer begins dating a 20-something.
Scotty Boom, a Chew Network super-chef, challenges Homer to a smoke-off. But when someone steals Homer's secret weapon - a smoker he bought off a mysterious man at a BBQ shack - Lisa and Bart are on the case.
Upon learning that their father really died of lung cancer, Selma and Patty agree to quit smoking. When Selma relapses, an angry Patty moves in with Marge and Homer
When Lisa becomes scared at the Krustyland Halloween Horror Night, Homer is forced to take down his Everscream Terrors decorations. Halloween pop-up employees seek vengeance on Homer for causing them to lose their jobs, and rob his house while Homer and Lisa hide out in the attic. Homer and Lisa light up their stored holiday decorations to attract attention and stand up to the intruders.
In the annual fright fest Halloween episode, Sideshow Bob finally kills Bart, only to reanimate him; Homer wakes up with short-term memory loss; and Lisa, Bart, and Milhouse get super powers from radiation.
Lisa befriends Harper, a new kid at school who happens to be super-rich. Then, Homer befriends Harper's dad and is able to enjoy the perks of Lisa having a rich friend, as well. But Lisa decides that Harper is a bully and moves to end the friendship, which prompts Homer to try and smooth things over so he can continue to enjoy the good life.
When Homer loses $5,000 at a poker game with Broadway legend Laney Fontaine, the only way he is able to settle the bet is if he loans Lisa to Laney for a month. Then, Laney turns Lisa into a show biz kid and Marge and Homer fear they made a mistake letting her go. So they head to New York to get her back.
Lisa sets out to restore the tarnished reputation of Springfield's first female inventor. To find her invention, she scours an abandoned asylum and a restaurant that caters to men. Bart joins Lisa at the asylum, stealing one of the homicidal patient's notebooks, and bragging to the boys at school that he wrote the entries himself.
Bart's coming of age story, a la "Boyhood," chronicles his life from six years old to his time as an accomplished young man. Along the way, his tense relationship with Homer, an overly uncaring version of himself, and Lisa, who overshadows him in every way possible, shape Bart more than he realizes
After a photo Marge posts on social media gets Homer fired, he returns to the best job he ever had, a dishwasher at a Greek restaurant. This same post inspires Lisa to code an app that predicts the real-life consequences of anything you post online, only to create sentient artificial intelligence
There is a new teacher at Springfield Elementary, and a captivated Bart tries everything to win her over. Meanwhile, Homer decides to buy a new brand of "milk," which causes early puberty, both for Bart and Lisa.
Sanjay passes his stake in the Kwik-E-Mart to his millennial son, Jay, who turns it into a hip, health food market against Apu's insistence on tradition. Bart, whom Homer had convinced to give up pranking, is called upon to return to his trickster life and take down the new store.
Lonely Professor Fink uses science to turn himself into a man whom women find attractive. Then, overwhelmed by the attention, he invents an algorithm to perfectly pair the lonely men and women of Springfield, realizing that scientific exploration is his true love.
Meanwhile, Marge, Bart, and Lisa visit Grampa for Valentine’s Day and try to rescue the old folks from a drug-induced hallucination that allows them to relive their happiest memories.
After Bart accidentally sends a sweet homeless woman’s cart into the river, he allows her to live in his closet for a small fee. When Lisa discovers that the woman is an incredible folk singer, she offers her own closet and plans a concert, only to be disappointed by Hettie’s surprising substance abuse and violent nature.
Meanwhile Homer tries to prove he’s handy, but accidentally traps the cat in the walls of the house.