Marnie and Desi sit on their bed, in a fight because Marnie didn't want to get scones with Desi that morning. Desi doesn't understand why Marnie is being cold to him and wants her to connect with him. Marnie is annoyed and wants some space. They argue more and Marnie storms out, with Desi shouting after her.
Marnie walks aimlessly, listening to music. A group of guys hanging out on the street catcall her and she's surprised to see Charlie among them. She tries to walk away but he follows her. She tells him she's married. He tells her that it's beautiful. She asks what happened to his business and he tells her that it wasn't for him. He ended up getting no money from the business.
Charlie invites Marnie to a party with him uptown. Marnie scoffs and yells at him, calling him an asshole for what he said to her when they broke up. Charlie explains to her that he was going through a hard time when he did that because his father committed suicide. Marnie is moved by that and agrees to go to the party with him.
Charlie insists that they need to get Marnie a dress. They go into a store and Charlie leaves to use the bathroom next door. Marnie tries on one red dress and when Charlie comes back in, he grabs her, throws money on the counter for the dress and they leave quickly saying that "they" are waiting for Marnie and Charlie.
Marnie and Charlie arrive at a fancy black tie affair and Marnie is confused. Charlie explains that he's stopping by to see a friend. Charlie and an older man speak privately, the older man referring to Charlie as "Brian," while the older man's fiancee Masha informs Marnie that Charlie is selling her fiance cocaine.
Charlie again abruptly goes to use the bathroom. Marnie introduces herself as "Magita Perez" to the older man and Masha. The older man asks if Marnie would like to join him and Masha upstairs, implying "Magita" is a hooker. Marnie goes along with it and gets $600 from the man, agreeing to meet them upstairs in an hour.
Marnie and Charlie leave and use the money to eat a fancy, expensive dinner. They dance in the restaurant. Marnie looks comfortable and happy with him. She tells him that he's gained weight and she likes it.
Marnie and Charlie walk through the park. She tells him that half her album was about him and that he was her family. Charlie sneaks into the boat area and they steal a rowboat, though Marnie is hesitant to steal a boat that isn't theirs. Charlie rows them out. They kiss. The boat tips over and Charlie "rescues" her from the two feet deep water.
As they walk in the street, Marnie is robbed by a man who seems to be tweaked out and has a gun. He takes her engagement ring, wedding ring, and purse. Charlie voluntarily gives the man Marnie's earrings as well.
Marnie and Charlie go to Charlie's disgusting apartment. Marnie notices that he has garbage bags on the windows. They lie in bed together and Charlie brings up the two of them running away together. Marnie considers it, saying that she doesn't need any of her stuff. Charlie tells her that they'll go when the sun comes up. Marnie and Charlie have sex.
Marnie leaves the room to shower in the bathroom, which is in the hall. She talks to a girl who enters the bathroom while she's in there. The girl complains about the lesbian she was with who kicked her off of her motorcycle on the side of the BQE.
Marnie returns to the room and starts tidying up. A needle falls out when she moves Charlie's pants and when she asks him what it is, he claims that he's diabetic.
Marnie leaves and goes home with no shoes, wearing the red dress. She runs into Desi on the stairs of their apartment building, and he asks her where her rings are. She tells him that she doesn't want to be married to him and that she knew it when she married him but didn't want to give up on another dream. Desi breaks down and sobs. Marnie offers to pack a few of her things and go so he doesn't have to leave the apartment.
Marnie lets herself in to Hannah's apartment and climbs into bed with a sleeping Hannah and Fran.