The Cerritos is escorting an emissary to trade talks. The Emissary is a Doopler and will duplicate involuntarily in stressful situations which has the crew very cautious.

Captain Freeman has an eye on attending the Command Conference on Starbase 25.

Mariner wants to go to the Conference afterparty but she and Boimler are on stacking crate duty. She realizes that Boimler's transporter clone won't be able to make it so Boimler should go and take her as his plus one.

Rutherford and Tendi work building a model of the Cerritos in their downtime.

As they arrive, Captain Freeman accidentally spills her real feelings about the Doopler guest where he can hear her and he begins duplicating out of shame. The Cerritos is blocked from docking until the Doopler is returned to a singular form.

Boimler wants to wear skants to the conference. With the Doopler situation, Mariner uses the chaos to cover their beam down to the Starbase.

The location of the party is secret so Mariner and Boimler set out to find it. A hooded figure sees them from afar and radios in a message that Mariner is back.

In a shop, Boimler and Mariner are confronted by Melvis, an old colleague of Mariner's with a grudge. He and Boimler bond about how difficult it is to work with her.

Melvis knows where the party is but he needs Mariner and Boimler to move some merchandise for him.

Rutherford keeps finding notes from past him about the model.

The Dooplers are moved to the lounge for holding. Rutherford and Tendi try to find a new place to work.

Mariner is annoyed that Boimler shared information with Melvis. She still holds a grudge about Boimler going to the Titan.

They're pulled over by station security. Melvis hid illegal weapons under the other goods in the crate. Mariner decides to run for it.

Rutherford and Tendi try to escape the burgeoning number of Dooplers. Rutherford confesses that his memory gap makes him feel like he's competing with his own ghost.

Mariner and Boimler's chase ends in a pond in the space station's aviary biodome. Mariner contacts Melvis and threatens to tell station security about his weapons trade. He coughs up the location of the party.

Boimler gets in but Mariner is barred. They have an argument and Boimler heads into the party, angry. At first, he's excited but then he feels lonely.

Tendi tells Rutherford that old him never finished the model either. They just used the activity to get people to leave alone. Rutherford uses the models warp core to break open an escape hatch seal and they escape the Dooplers.

Boimler finds Mariner in a bar. They reconcile.

Freeman realizes that anger make the Dooplers recombine. Once the Doopler is down to a single individual, shea nd the bridge crew head to the party.

In the bar, Boimler and Mariner are impressed and cheered up to learn that Kirk and Spock once got barred from the same party and ended up drinking there.

Freeman discovers that she's not on the list. She gives a big speech but still doesn't get in. They end up outside the bar eating meat on a stick. Mariner comes out and invites them in for a drink. The Doopler approaches them and thanks Freeman for de-duplicating him. He asks for a suggestion as to where he could hang out for a few hours. Freeman has him transported into the party.

Tendi gets Rutherford a model of DS9 to work on.

Mariner tricks Boimler into admitting he's her Number One.