Woo-hoo Dunnit?

"Woo-hoo Dunnit?" is the 22nd episode of season 30. It aired on May 5, 2019.

Plot
A documentary crime series, "Dateline: Springfield", is interviewing the Simpson family after Marge and Lisa, returning home, find that Lisa's college funds that were hidden in a can of kitchen cleanser under the sink, were gone. The police were called and Chief Wiggum and Lou investigated, but when the narrator says that the suspicion turned toward the Simpson family, Marge gets angry at the accusations.

A call to the police made by Helen Lovejoy brings Marge to the top of the list of suspects, accusing her of using the money for her gambling problem, though surveillance cameras showed that even if she went to the casino, she resisted the temptation and walked out. (However, the surveillance footage appears to show Helen herself at the casino, smoking and drinking while playing a slot machine.)

The next person on the suspect list was Homer, due to his tab at Moe being cut off, and Lou suspected he found the money in the can of cleanser while cleaning the kitchen after smearing the walls with spaghetti sauce from his dinner, and used the money to pay his tab. With the ruse of granting admission to a Super Bowl viewing party in exchange for a pair of pants, the cops got his pants, but found no evidence of money on them.

Dateline: Springfield looked at Mr. Burns next, but with him being a bilionaire, $600 would have been nothing. Next, Moe accused Homer directly, but the police find out Homer had an alibi: he had made a six-hour call that night to Disco Stu by mistake, and he had licked the walls clean of the sauce without using the cleanser.

The next suspect is Bart, who was accused by Milhouse of buying Slime with the money. Bart knew of the money under the sink but always paid back what he borrowed. He is then seen as the mastermind behind the production of green Slime (ala , at Springfield Elementary. But when the market price fell, he sold his remaining inventory of the Slime to Comic Book Guy and put the money back in the can.

The final suspect of the family was Lisa, who was accused by Martin. They went to King Toot's Music Store and he showed them her trying a new saxophone to buy, but Lisa didn't buy it. Krusty did to show to his father but failed. Lisa's alibi was that Marge took her to a hopscotch tutor.

With all suspects gone, they kick Dateline: Springfield out, asking for an apology and getting it, and for them the mystery was unsolved. Marge and Homer are seen watching the documentary, and Marge places a snap-on coaster under Homer's drink.

It turns out that she invented them and wanted to start a business, with the coasters costing $0.65 a piece. Homer finds out Marge was the culprit, stealing the money to invest in the business -- "gambling on herself", so to speak. Homer covers for Marge and lies to the kids, saying rats ate the money, and then goes to the beach and enjoys a stroll with Marge. Meanwhile at the studio, the narrator loses his voice after arguing about the unresolved end of the show, and gets a vocal cord transplant from a sheep.