The only logical explanation there is as to why Lena Dunham consistently writes Marnie as the one of the most unlikable, aloof, and deeply toxic characters on television is that Girls is really just a slow-simmering revenge plot against Brian and Allison Williams. I jokingly threw out this theory back in November when all we had was a trailer. Now, three episodes into this uneven season, I just have one question: What kind of dirt does Ms. Dunham have on the Williams family? 

The answer to that, like many questions about this tumbly season of Girls, is unknowable. Like, when did Marnie become so unconsciously rude? And why Hannah, the number-one target of Marnie's rudeness, thinks it a great idea to put this beautiful monster in charge of her 25th birthday is beyond me. A monster who says things like this about you, in front of you to other people on your birthday: "I keep telling her she can look like this every day if she wanted.” A monster who yells at YouTube customer service associates. A monster who forces you to sing a song from Rent so she can hog your birthday spotlight.

In seven minutes or so of screen time, Marnie managed to do all of that. And when it comes to Marnie's/Williams's singing, it's treated not unlike her rendition of "Stronger" — aggressively embarrassing. The biggest problem with all this overt meanness and assertive rudeness is that I don't buy it. I have a hard time believing that Marnie, after what she went through in the first two seasons (a break-up, being assaulted by an art installation, getting fired, getting dumped again, having Hannah pick Adam over her) wouldn't learn from those lessons. I could also be giving Marnie just too much credit. 

Hiding in the shadows of Marnie's rampage was the rest of the episode, which wrapped itself around the introduction of Caroline Sackler (Gaby Hoffmann), Adam's sister. Caroline, who allegedly euthanized her and Adam's grandmother, spills into Adam and Hannah's love nest after making a frantic phone call and flashing a leopard-pattern of bruises on her leg. "She destroys everything in her wake," Adam tells Hannah, possibly referring to his grandma and maybe foreshadowing their relationship.

Even with the volume of all of the characters turned up — Ray is dopier than ever, Shoshanna as wholly ditzy as ever, Marnie (we went over this), and Hannah as selfish as ever — Caroline sticks out. That isn't because the episode leaves with her naked, full bush, and crushing a drinking glass with one of her bare hands, but because she gives us some insight into Adam, and perhaps an explanation of why he treats women the way he does. I wouldn't put it past Hannah to try and game Caroline's visit to her advantage.  

We've seen Adam with Hannah, Natalia, and now Caroline. And grandma-killing, glass-crushing Caroline kind of explains his reluctance to trust women (probably a good idea with Caroline) and why he discards women the way he does — saying goodbye to something you don't love is a lot easier than putting in the effort into cultivating a relationship and watching the bottom fall out. 

The last few gasps of the episode are eaten up by Hannah's parents, whose tics, like the other characters', are blown out to a point where they're hardly recognizable. And then there's Shoshanna. A Shoshanna who apparently yells out, "Hey, hottie. Do you know where I can find some dank weed?” to random boys and is equally callous to her friends. "It's really amazing that all three of you have accomplished so little in the four years since college," she says. The search for recognizable humanity in this Girl continues.

In a sense, you almost don't want to blame Marnie for acting the way she does, because she could just ultimately be a reflection of her self-absorbed, churlish friends. After all, Shoshanna is supposed to be the nicest one and she is just a nightmare this season. But I'm still betting Dunham has some incriminating photos (not of the Vogue variety) somewhere.