Homer is initially happy to get an organized, cheerful new assistant at the Springfield Nuclear Power Plant, a very tall woman named Roz Davis. However, when he and Barney head out to see a film during their work shift, Roz reveals this to Mr. Burns, who demotes Homer to Roz's job and gives Roz Homer's position. Roz proceeds to charm the regulars at Moe's Tavern while finding dozens of ways to make Homer's job miserable. After Ned Flanders sees Homer is depressed, Homer tells him about Roz, and is shocked to learn that Ned knew Roz back in Ohio; they were part of the same Christian group, and when Ned gave her a congratulatory hug for winning a "no-fun run" he learned that Roz cannot stand any physical contact. When Roz wins a "Worker of Millennium" award at the plant, Homer manipulates Burns into giving Roz a hug. She proceeds to beat Burns up, and is fired. Roz then compliments Homer for being much smarter than she expected, in terms Homer does not quite understand.
Elsewhere, Bart is not ready for the upcoming Springfield Elementary science fair. He ends up working with Martin Prince and after Bart comes up with a general idea—cool robotics—Martin does all the work and constructs an adorable robotic baby seal. However, it is revealed that when the wiring is tampered with, they become violent attackers. The seal wins first prize at the Fair, to Lisa's disdain. When she goes to the Springfield Retirement Castle to whine about the injustice to Grampa, the seniors citizen see the seal visibly cheer up Jasper and the value of the invention becomes clear. All of the senior citizens then get their own seals, and they become happier and healthier, which angers a consortium of local businesses (led by the local funeral home) who want the oldsters to go back to being miserable and more rapidly dying. The group figures out the wiring secret and reworks the seals so their fury returns, even causing the death of Mrs. Glick. Chief Wiggum has all the robots impounded. Bart and Martin enlist the aid of Professor Frink who then gets a larger group of nerds to remotely hack into the robot software and make them nice again. They succeed and as a result, Chief Wiggum releases all the seals, who return to the nursing home.