Lisa gets invited to work at an institute and get away from her crazy family.
Lisa is explaining to a few scientists about Einstein's theory of time travel through wormholes. She explains that she's close to figuring out how to solve the theory, but is constantly getting interrupted by her siblings asking her for advice on various subjects. When Lisa explains that she's having a hard time doing research because of her siblings' interference, one of the scientists, Dr. J, asks her if she wants to visit the science institute, since she can continue her studies without interruption, and Lisa accepts.
At the science institute, Lisa is given the tour of the institute, and gets to continue her studies in the institute's research lab. Happy with what she's seeing, Lisa breaks out into song about all the wonders of the institute. After explaining to the scientists Einstein's theory of time travel, Lisa prepares to head back home, but Dr. J offers her the option of staying at the institute full-time, and Lisa take this into consideration. Lisa calls up her parents via video chat, and is explaining her desire to stay at the institute, much to the aghast of her family. Lisa, expecting this kind of reaction, shows them a chart explaining that 97% of her psychological makeup consists of scientific pursuit, whereas her emotional attachment to her family is a measly 1%. Realizing how much she values research and thinking she's "independent" enough, Rita and Lynn Sr. agree to let Lisa stay at the institute.
While doing work, Lisa gets hungry and decides to get some dinner. Expecting a proper meal, Lisa is disappointed to learn that her dinner is a gelatinous cube consisting of vitamins for necessary brain efficiency and ice cream that is injected into her body instead of eating actual ice cream. Later, Lisa wants to watch The Dream Boat with her colleagues, but due to having no interest in the show, they abandon her. In her room, Lisa is unpacking her bag when she comes across a jar of peanut butter mixed with jelly with a note attached. Seeing that it's from Lincoln, since he would make her PB&J sandwiches before bedtime, Lisa tries to make a PB&J sandwich. Much to her dismay, she finds that she's unable to do so. While getting ready for bed, Lisa is unable to zip her pajamas on, since Leni would usually do that for her. When Lisa lies in bed, she's unable to fall asleep. She remembers how Lori would read a story to Lily that would not only help her fall asleep, but Lisa as well. While sleeping, Lisa has a nightmare and tries to tell her parents. Alas, since she's at the institute, they are not there to comfort her. Lisa, having to resort to sleeping with a model skeleton for comfort, begins to cry, realizing that it could only mean one thing.
Calling up her family again the next day, Lisa takes back what she said about her psychological makeup and shows them an updated version of her chart, where her emotional attachment to her family exceeds her scientific pursuit. She explains that she misses her family and expresses her desire to come back. The family, happy to hear the good news, encourage her to come back home. Unfortunately, Lisa explains that if she were to return home now, her reputation will be damaged. When Leni brings up the idea that Lisa should travel back in time to before she ever went to the institute, Lisa, realizing that she solved Einstein's theory of time travel, attempts to do so.
After getting her time machine ready, Lisa activates and programs it to send her to yesterday. The portal successfully opens up, and Lisa jumps in. She is transported to the day before, just before Dr. J offers the chance to visit the institute. When Dr. J asks Lisa about this opportunity, Lisa politely declines, saying that she's perfectly fine at home. Lisa, while admittedly annoyed by some of her siblings' antics, is more than happy to be "home, sweet home."
‣ Happy Forest - Werner Tautz and The Heinz Kelssing Orchresta [Plays when Lisa enters the lunch room]