Ted's plans to make his own design firm in his apartment hit a snag when his personal assistant begins sleeping with Robin, and Marshall tries to find a way to make himself indispensable at his workplace.

When Marshall finds out he's the "reacher" in his relationship with Lily and not the "settler," he considers pursuing a sexy and cool female coworker. Meanwhile, Ted finds out Robin is a drinking game for his architecture students.

The Captain asks Ted to help find out who stole Zoey away from him, Marshall withholds sex until he does something to help the environment, and Barney is reluctant to admit that he has a crush on Robin's friend.

Despite Zoey still opposing the new GNB headquarters being built on the Arcadian Hotel site, Ted and Zoey's personal relationship is thriving. That issue is only one of the many disagreements in their life, which Ted likens to the two challenging each other mentally. On the other hand, he sees Marshall and Lily's relationship as being boring, as they agree on everything to the point of them almost melding into one person. Lily and Marshall, on the other hand, see their relationship as being supportive, the way that relationships should be, whereas they see Ted and Zoey's relationship as being too much work to the point of being mentally exhausting. But Marshall quitting his job at GNB to work in a non-paying volunteer position at the NRDC and Zoey managing to get the Landmark Preservation Society to agree to a hearing over the GNB project may change everything on both sides. Meanwhile, Barney seems to be taking Marshall leaving GNB the hardest. He admits to Robin that his anger regarding Marshall's departure has to do with a meatball sub.