Crystal Blue-Haired Persuasion

"Crystal Blue-Haired Persuasion" is the 23rd episode and season finale of season 30. It aired on May 12, 2019.

Plot
At the Power Plant, Smithers delivers Mr. Burns the financial report, and is lower than expected, and to solve it, Burns cuts off children health care from worker's benefits and releases the hounds.

Due to this, the children medicines had to be cut, including the ones for Bart's ADD, getting a cheaper one, however Lisa shows Marge a video from hypochondria.edu, starring Walter Hotenhoffer, showing the side-effects of taking that lower cost medicine, and they start manifestation on Bart.

Dr. Nick is no help with the situation, but at a crystal shop, FAO Quartz, they discover blue healing crystals for its problem. 3 weeks later Bart takes home an "A" on a paper, demonstrating the powers of the crystals.

Marge goes to buy more crystals, but the shop is closing, and the owner gives Marge the entire inventory, while she joins a new cult. She cleanses the crystals and start selling them and the clients are happy at the new Ye Olde New Age Store, held in the garage.

When materials are going down, Lindsey Naegle appear and offer her to expand her businness, becoming the Murmur store, which has a huge success, so much that Homer rolled on it on their bed and they start imagining a journey through a blue crystal world, including marrying again.

Lisa keeps being skeptical about the powers, while Piper Paisley, the owner of a healing beauty relaxorium in Shelbyville, Plop, menaces Marge on getting out of the business. When a rock saying peace gets thrown in the house, Marge decides to open up a kiosk at the Shelbyville Mall besides Plop.

After school ends, Lisa finds out Bart's plan, by using the crystals agains the painting on the walls, revealing the text that Bart read while Milhouse distracts Ned. Bart has to confess to Marge his plot, with Lisa making him understand he has to do it cause Marge is the only one who still believes in him.

In the war between kiosk, Marge sends Patty, Selma and their mother against Plop, when Bart arrives and confesses the truth, while Mrs. Muntz and Luann arrives showing her it's true that the crystals didn't have any power, and she decides to close the kiosk.

At home, Homer is seen exercising, confused on his working role, and Marge clears up his confusion, and then goes to the cult house to make sure the shop owner was ok, but it wasn't and she told her to run and people started shooting at them. They get in the car and run away. The nun then blows up the bridge to the house.