Warning: Major spoilers ahead

In class, Greg listens to his students read their stories in the style of beloved authors, but notices Tommy isn’t there. As he dismisses the class (and takes back the watch from Spooner he drunkenly gave him the other night) it seems the students are warming up to him – with even Ronni admitting she “didn’t hate” the class. Taylor reckons it’s because he got laid, and while he doesn’t confirm it, she’s not wrong.

Greg later runs into Tommy, who claims he missed class due to “an emergency”, but folds when Greg asks a simple follow-up question. He tells Tommy to be a better liar.

Delivering a hot chocolate to Cristle, she’s worried it’ll look like a sign they hooked up and tells him to take it back. Armed with two cups of hot chocolate that he insists are for himself, he sits in on a meeting with Walt and Dylan about the upcoming dedication ceremony for the student centre – where his ex-wife, Elizabeth, will be honoured. Dylan notes Walt is worried she’s coming for his job. Greg has no intel on her motives as they haven’t spoken in years. He blames himself. She tried to be civil after their split, but he couldn’t bring himself to.

At Greg’s lodgings, Katie notices he has brought a photograph with him from his home in Florida and has hing it on the wall. She mocks him for bringing it as, being an art history professor, she can confirm it’s worthless. He tells Katie that her mother is coming for the weekend and suggests the three of them hang out. Katie’s nervous because the last few times they’ve tried that haven’t worked out great, but he assures her it'll be fine and it’s time to move forward. Katie then takes things a step further, calling up Elizabeth and, without running it past Greg, volunteers his place as somewhere for her to stay. Greg is embarrassed but ultimately lets her and promises to “not be weird”.

After getting a suggestive text from Archie, Katie pulls him out of class so they can talk. She’s insistent they will never hook up again, but he’s not so sure. When they get to his office, he sees yet another tag on the door of his office saying “For Katie” and asks if she knows who is doing it, but she has no idea.

While Katie is insistent she’s over him, the new green policy automatically shuts the faculty building’s lights off at 7pm and she uses the opportunity to leap on him.

The next day, Walt leads the Elizabeth Stoddard Student Centre commemoration, introducing Elizabeth who makes a speech on stage. She notes her pride at leading the green initiative and is looking forward to spending more time at the campus. However, her speech is interrupted by Greg’s phone going off – with his ringtone changed to 50-Cent’s P-I-M-P by Spooner during their raucous night out.

As the family walks through campus, Liz notices one of the students referring to Greg as “Rooster”, and wonders why. Katie jokes he’s “cool now” and even caught him on a “walk of shame” a couple of nights before. Greg’s embarrassed but doesn’t deny it. As they prepare to go their separate ways, Greg encourages a family fun night with the three of them, and Liz agrees.

Sunny arrives back at her apartment following her interviews in New York, and roommate Mo is excited to hear all about it – it becomes clear Archie didn’t ask her how it went the entire taxi ride back. He excuses himself by saying he spent the weekend writing, but Sunny can tell something’s up, and Mo slams him for changing the conversation back to him. Sunny asks Archie to “help her unpack” (discretely instigating sex), but Archie makes his excuses and leaves. Mo begs Sunny to dump him, even offering to change the apartment locks, but she says even if she did, she’d still see him on campus. However, she agrees “f**k that guy”.

Greg takes Liz to Walt’s office for a meeting, where Cristle pulls him aside to “sign a form” about his professionality at work (which is, in reality, a photocopied picture of her breasts). Liz tries to charm Dylan, saying how great it is to have a female Dean, and how good it would be to have a female president in Walt’s office someday. Walt nervously agrees and says Dylan will be her chaperone for the day as he has to deal with the alcoholic hockey coach. Liz offers Greg up as a replacement, revealing his past as a minor league player. Walt is hurt as Greg never mentioned this and had told him he was not a hockey fan to get out of attending a game with him. Despite attempting more excuses, Liz strongarms him into agreeing.

Archie is in his office when he notices someone loitering outside, and when he goes to investigate, he realises his office has been tagged once again with “For Katie”. He chases the hooded assailant through the college, failing to catch them but noting they are wearing a pair of punk Converses. Katie witnesses this, and texts Archie to suggest another hook up.

As Katie waits for a response in the student centre, she spots Sunny, who comes over and introduces herself. She apologises for sleeping with Archie, but Katie is dismissive. Sunny pushes on, saying Katie didn’t feel like a real person to begin with, more like “an abstract idea from someone else’s life”. But now she knows Archie still has feelings for her, and Katie must be unsure how she feels about him. Sunny admits she messed up both Katie’s life and her own as a result of sleeping with Archie, and she only has herself to blame. Katie softens and says Archie takes some of the blame too. Before she leaves, Katie asks about how she’s getting on with the pregnancy. Sunny admits she’s scared, but pushing through. Archie, who spots them talking, quickly exits before he’s noticed.

At Greg’s house, Liz encourages Dylan to try and get the Ludlow Review back as a physical paper, rather than online. Noticing some chemistry between Dylan and Greg, she openly wonders if it was her he had sex with. Greg is quick to shut it down, but the news shocks Dylan, who is keen to know who it is. For her part, she mentions her date from the party, but then downplays their relationship, saying he was boring, a bad kisser, and that she hates him.

When Liz gets a message from Katie saying she needs to talk to her, it becomes clear she’s not coming, which upsets Greg who was relying on her for moral support. Liz knows he’s freaking out, and the girls gang up to mock him. When Liz tells Dylan that she’s glad Greg has her, because he only had two friends while they were married, he snaps that he was only left with one because she slept with the other. Dylan calls it a night and heads home.

Archie visits Walt in his sauna to complain about the “For Katie” tagging going on around campus, but Walt is irritated by Archie’s enviable physique, which seemingly comes from no exercise or diet regime. When Walt asks how Sunny’s interviews went, Archie doesn’t know, simply saying “fine”, prompting the mentor to sarcastically call Sunny a “lucky girl”. Walt mocks Archie for letting the tagging get under his skin and to not let it, before kicking him out.

Liz and Greg have erupted into an argument, with Greg trying to downplay his previous comment as him “razzing on her” like she was on him. Liz says things weren’t great when she blew their marriage up, and while she takes responsibility for that, and feels terrible he felt lonely, she has a big career and wasn’t willing to give that up for a boring life with him. He tells her he didn’t want to rehash it this weekend, but doesn’t know if they can stop.

Greg shares his desire to “get to a sweet spot” where they can be friends, which they were until this fight, and asks for a second chance to make that happen. But Liz says they should cut their losses and leaves to see Katie.

When Archie spots one of his students wearing pink Converses, he approaches her to talk. The student, Liz, mistakenly thinks that he’s hitting on her as he takes her into his office. When the 7pm light shut off leaves them in darkness, he switches the light back on to find Liz whipping her shirt off.

He horrifyingly tells her to put it back on and leave. She storms out but accuses him of giving her “mixed signals”. The entire thing is witnessed by Zoe – one of Katie’s students - who is sitting outside, and he quickly heads back into his office, which has been tagged yet again with “For Katie”. Zoe, pleased with herself, walks off in pink Converses.

Archie is later pulled into the office by Dylan and Walt for a disciplinary meeting. Ruling that Archie was not at fault, Dylan decides to put a hold on the green initiative on campus while they research best practices. Walt realises this means that she can get the Ludlow Review back in print, and he congratulates her for figuring a way to do it.

Dylan confirms the student called it a misunderstanding, but Archie puts his foot in it by saying he would never sleep with a student. With both knowing about Sunny he clarifies she’s not his student and she is a post-graduate. He then swiftly leaves.

Katie tries to have a heart-to-heart with her mother about Archie, but both women admit Greg is the one to talk about feelings with. Katie admits feeling guilty for sleeping with her own husband, but Liv says, as the Archie in her own marriage breakdown, she’s hardly the one to talk about it. Liv admits she can be selfish and makes decisions just for herself to be happy, which doesn’t always work out for her, but Katie has a kind heart.

That evening, Greg joins the hockey coach on the ice for practice, who is clearly struggling with remaining sober. He’s introduced to the team and is touched to see Liv and Katie there to support him. So much so, he has a lapse in concentration and gets a hockey puck in the mouth.

That night, the three head to Greg’s house, where they tend to Greg’s swollen mouth as he drinks through a straw. As Katie grabs a drink in the kitchen, Greg and Liz share how much they love their daughter, and how well they raised her.

Greg invites Liz to Thanksgiving and she considers it, but the moment gets awkward when Katie notices the photograph she mocked earlier had been taken down from the wall. When she replaces it, Liz recognises it as a photo they took in Italy together – and she’s the woman pictured in the hat.

When she asks why he still has it, he says it makes him happy, and they all realise that Greg is still in love with his ex-wife. Liz takes her leave, and when she does, Katie apologises, realising her dad is struggling more than he let on after the split. He admits he is struggling, but promises he’s getting there and praises her for the “clean break” she had with Archie, not knowing the truth. The pair have a moment together on the sofa.