A Romulan ship cruises through space. Their lower decks crew complain about cleaning up after the torture of a Reman. The ship encounters the unknown vessel and is destroyed in a similar manner to the Klingons.

On the Cerritos, Shaxs and Ransom are stretching out in unitards. Shaxs is concerned about his relationship with T’Ana. Ransom comments that Mariner won’t be his problem for long which Mariner overhears and interprets to mean he plans to demote her.

Mariner returns to the ensign bunks where the others are packing up to move to their lieutenant quarters. Tendi and Boimler are waxing nostalgic. Mariner shares the news Ransom plans on demoting her. She plans to earn her demotion rather than waiting for him to call her on some minor infraction.

Boimler and Tendi gather their things cheerfully but are saddened when they realize Rutherford wasn’t promoted with them and can’t move into new quarters too. He tells them not to worry, he’ll just get a promotion that day and join them.

Mariner meets up with Ransom and Ensign Gary for a mission still wearing her workout gear. Their mission is to rescue some humans from a menagerie, a zoo assembled by an alien.

Boimler finds his new quarters and discovers it faces onto the nacelles and is constantly flooded with bright red light.

Mariner does her best to push Ransom’s buttons, but he stays calm.

They meet the menagerie’s owner, Narj. Mariner asks him about a cute looking alien called the Moopsie. She accuses him of imprisoning all the creatures in his menagerie.

In Engineering, Rutherford tells Tendi he’s keen to be the same rank again. Tendi tells him not to feel pressure to get a promotion.

When Rutherford shows Billups his work, it turns out a new guy, Ensign Livik, did him one better, improving the warp manifold by a factor of .06 (versus Rutherford’s .05). Billups fires up the new protocol causing the light in Boimler’s room to become even brighter so his visor is useless.

At the menagerie, just as he’s about to release the humans, Narj notices that the Moopsie is out of its containment and freaks out. It gets in with the scary looking Swamp Gobblers and drinks their bones. Everyone runs.

In Engineering, Livik continues to one-up Rutherford.

Boimler gets Shaxs to change his room assignment. His new one is next to the holodecks. The walls are thin and he can hear everything happening in the holodecks during T’ana and Shaxs kinky, kill-happy date. When he moves to the other side of the room, he’s treated to Captain Freeman’s presidential inaugural scatting.

Mariner, Ransom, Gary, and Narj hide inside a metal-door-enclosed refuge space. Ransom accuses Mariner of releasing the Moopsie. She denies it but admits to giving him insubordinate behavior reasons to demote her.

They have it out. Mariner tells Ransom she heard him say she wasn’t going to be his problem anymore. Ransom says he meant he wasn’t going to take the bait, that she always self-sabotages after she gets promoted and he wasn’t going to let her do it this time.

Gary accuses Narj of setting the Moopsie free. While Narj is denying this, the Moopsie knocks out a ceiling vent and jumps down onto Narj, drinking his bones.

Ransom, Mariner, and Gary run out of the refuge and shut the door, trapping the Moopsie inside. Unfortunately, the refuge turns out to be the station’s main control room. The Moopsie begins hitting buttons on the control panel and the station begins to fall out of orbit.

Boimler’s living inside a Jeffries tube because his rooms haven’t worked out. Rutherford comes across his encampment and tells him about his newest Engineering goal but Boimler lets him know an ensign just came through doing the same thing.

On the falling station, Mariner intends to lure the Moopsie out by sacrificing herself. Ransom hits on a plan and has Mariner punch him until his teeth fall out. They use the teeth to lure the Moopsie out of the control room and back into its containment.

Tendi tries to get Rutherford to stop working so hard for a promotion. When he tries to tell Billups about his newest innovation, Billups tells him to wait until after he’s promoted Livik. Rutherford gives up and apologizes to Tendi. She assumes superior rank attitude and orders him to stop trying so hard because they will always hang out and have fun together.

He hugs her and comments that he wishes he hadn’t turned down all the promotions he’d been offered in the past for good work. He’d turned them down so he and Tendi and the gang could stay together.

Tendi asks why he can’t accept one of those past promotions now. He demurs, but she shouts it out to Billups who says yes, telling Livik maybe next time.

Tendi gives Rutherford the pip and leads a cheer in his honor. Livik is left fuming.

On the station, once the Moopsie is secured again, the station’s orbit is stabilized, but they still don’t know how the Moopsie got out. Gary comments that humans are always being blamed but they aren’t always at fault. Mariner notices a panel in the humans’ containment space is upside down and realizes the humans rewired the Moopsie door which led to its escape. So humans were at fault.

Mariner, Ransom, and Gary leave the humans in the menagerie until the next Federation ship can pick them up. They’d planned to kill Narj so they could take over the menagerie and reap the profits.

T’ana fixes Ransom’s teeth. Mariner and him make peace.

Now that Rutherford’s been promoted, he and Boimler decide to be roommates. Their quarters are once again facing the nacelles, but Rutherford is able to fix the viewport filters to block the intrusive light. Rutherford gets to work tinkering but once Boimler sees a bunk ceiling dent like the one in his ensign bunk, he feels right at home.