Due to The request by Penny to Sheldon and Leonard to accept a furniture delivery, both of them wait for it on the ground floor. Since the delivery man leaves directly after handing over the paperwork, Leonard and Sheldon are confronted with the problem of getting the delivery upstairs themselves. Since the elevator of the building is out of order since that small problem with the rocket fuel, Leonard and Sheldon have to get the heavy and unwieldy crate, in a strength-sapping and laborious act, up the stairs and into Penny's apartment. Sheldon is shocked by the condition and the untidiness of Penny's apartment when they enter it.. Since Sheldon cannot deal with the knowledge that chaos reigns next door, he breaks into Penny's apartment during the night to remove precisely that chaos. Leonard is awakened by the noise and gets to the bottom of it all. As he sees what his roommate is doing, he tries to put a stop to Sheldon. Of course, he fails in the attempt and so in the end they clean up Penny's apartment together.

The next morning, Penny notices what has happened during the night and is beside herself. Still, Sheldon is unaware of any wrongdoing, but is of the opinion that the nocturnal housekeeping has considerably improved Penny's quality of life. But then, at Leonard's urging, he apologizes to Penny. Nevertheless, he messes it up through his choice of words and formulation, so that it does not lead to an improvement of the situation. Penny says some things to both of them that can be understood as a termination of their friendship. Unlike Sheldon, that weighs heavily on Leonard.

Later on, however, Penny feels somewhat more at ease within her four walls and tells about her view of what has happened to Raj, who says nothing in response and undoubtedly is elsewhere in his thoughts. But since Raj does catch some bits of the conversation and also passes them on the Leonard, Leonard writes a note of apology, which leads to the three of them getting along again. To make amends in some small way, Leonard, Sheldon, Howard, and Rah decide to help Penny put together her newly obtained piece of furniture. While putting it together, the scientists realize that the bookcase is completely inefficient and begin to reconstruct a bit. After the plan has been fully forged, they go to pick up the necessary material and leave Penny alone in the apartment.