Lydia's whirlwind romance with her new boyfriend, Zac, catches everyone by surprise. Micah is caught in the middle of an ongoing feud between Moriah and his girlfriend, Veronica. Ethan has growing suspicions about Zac after learning about their plans for the future. Veronica seeks out the help of a secret new friend.
Veronica secretly turns to Olivia as tensions grow with the Plaths. Zac feels like an outsider when he tries to spend time with Lydia's brothers. Kim gets vulnerable with Barry about their unsettled divorce. Veronica spills the beans on the state of her and Micah's relationship.
Micah and Veronica navigate the emotional aftermath of Micah's infidelity ahead of a trip to Georgia for Lydia's surprise proposal. Ethan goes down memory lane with new girlfriend Teegan before confronting Lydia about her decision to marry Zac so quickly.
The Plath family comes together to witness Zac's surprise proposal to Lydia, but Zac's demands prove too much for Ethan and Micah. Moriah considers leaving Cairo. Grappling with Lydia getting married, Ethan and Micah sit down with Zac and ask some tough questions.
The fallout from Lydia's proposal continues as Micah and Ethan question Zac. Veronica confronts Amber and Ethan about the Plath's treatment of her and later reveals a big secret to Micah. Moriah enjoys a night out on the town with Barry before her big move to Montana.
Ethan and Amber arrive back in Cairo after the drama in Boca. Lydia goes wedding dress shopping with her mom and sisters. Micah and Veronica meet up to discuss their relationship. Kim and Barry discuss the intimate side of marriage with Lydia and Zac.
Lydia and Zac visit Micah and Veronica at their home hoping to build a better bond before the wedding; Ethan and Isaac have a fun double date with their girlfriends; Veronica stuns Micah in therapy with a scandalous allegation about Teegan.
With Lydia and Zac's upcoming nuptials, discontent grows amongst the Plaths. Kim and Isaac struggle to see past Zac's red flags. Veronica's unexpected attendance has everyone on edge, and Ethan makes a dramatic exit.
Zac and Lydia finally say 'I do' and share their first kiss; an unexpected confrontation leaves Lydia and Zac at odds with Ethan and Isaac.
Lydia and Zac enjoy their wedding reception; Veronica's accusations divide the Plath brothers; a family meeting turns into a family reckoning.
Tensions linger after the wedding as the family confronts Veronica; Micah faces tough questions about his relationship.