Megan and Mick arrive at the emergency room to find Kevin and Sarah in the back of an ambulance, holding their brand new baby. “Say hello to little Mick,” Sarah tells the proud grandparents, bringing tears to Mick’s eyes. The family joins them at the hospital to meet the new baby, only to be thrilled by the announcement that Mick and Megan are engaged. They’re planning to hold the big event right away at the B&B, and the honeymooners will then take their long-awaited trip around the world.
Meanwhile, there’s a chill in the air under the shingle of Keller & O’Brien; Margaret and Connor are on the outs. Connor took David’s father’s case without her approval. She is convinced that they can’t win and that Connor dismissed her opinion outright. Connor admits he shouldn’t have done it, but Margaret can’t get over that he ignored her altogether.
Bree is frantically searching for Luke, who has checked himself out of the hospital and vanished. His phone has been disconnected.
Mick has something important to tell Abby: he’s retiring. O’Brien Construction is now all hers. “I think it’s time for both of us to move onto a new chapter of our lives,” he tells her. They’re proud of each other for making the leap. Mandrake stops by the house to say goodbye to Abby. Since his dismissal, he’s decided to go in search of his own home. But Abby has an offer for him to consider before he leaves. She needs a right hand man to help run the construction business. Would he be interested?
Finally, Evan visits Abby to talk. He has “unfired” Mandrake, or tried to, but now Mandrake is pondering Abby’s offer too. Evan has been thinking a lot about his biological father, believing that his mother’s taste in men does not reflect well on John Osterberg’s character. His memories of his mother’s boyfriends are traumatic. When one of them hit his mother and then Evan, they frantically fled the house, only to be in the car accident that killed Evan’s mother.
Evan goes to meet John at the beach and apologizes for his behavior. John accepts, and they reminisce about Evan’s mom. John has wonderful memories of her and their time together. His own wife passed away three years prior and they were never able to have children, so he’s wondering about the road not taken. Noticing the rentals on the beach nearby, they decide to take a couple of kayaks out on the water.
That night, Margaret goes to see Connor. She has exciting news: she knows how to win the case. She’s gone through the evidence with a fine-toothed comb and has learned that Dennis’s friend, Byron, might be the person responsible for the set up. They’re back on the same page. The next day they deliver the latest to David, who is relieved there’s a ray of hope. David fills Jess in and tells her how grateful he is for her support over the past months. Jess has her own news to share: after much consideration, she’s ready for them to try and start a family. He is over the moon, and even more so when Jess reveals that they’ve already started the process. She’s pregnant.
As Connor and Kevin help prep for Megan and Mick’s wedding, Kevin reveals he’s applying for medical school at Johns Hopkins and the University of Pittsburgh. But first, Bree puts Kevin to work because Father Morgan’s car has broken down and he needs a ride to the ceremony. Megan is thrilled to have received a present from Nell in Ireland, who has sent a new hair clip to celebrate the day. It will be the “something new” for the ceremony, but Megan is dismayed to realize she’s missing the something old, something borrowed, and something blue. Bree covers the blue and the borrowed with her sapphire jewelry. Megan heads home to figure out the something old.
As soon as Megan arrives, she bumps into Mick, even though it’s bad luck for them to see each other before the wedding. Neither of them were supposed to be at the house, but Megan shrugs off the superstition. “We don’t need luck,” Megan decides, “because we have each other.” They spend a few minutes together looking out on the water, until Mick presents her “something old.” It’s her old wedding ring, which he kept after the divorce. He never knew why he hung onto it until now.
At the cottage, Bree finds Luke waiting for her. She’s stunned when he announces he’s leaving; their relationship is over. He’s doesn’t want to sully her life with his troubles. She is angry that he’s making decisions for her and dismisses the idea that he’s bad luck. “I love you,” she declares, “And I think you love me too.” She can’t understand why he’s doing this, but asks that he at least show up at the wedding for Mick. But he won’t be there; he wants to make a clean break. A brokenhearted Bree dissolves into tears as Luke walks away.
At the B&B, it’s time for the wedding. The two boys stand up at their father’s side, while the three girls help Megan get ready to walk down the aisle. As the ceremony begins, Bree is shocked to see Luke sneak in, looking handsome in a suit. Mick and Megan eloquently recite their own vows to one another as the audience of friends and family look on with tears in their eyes. The pair exchange rings for this second time and are pronounced husband and wife, sharing a kiss as the onlookers applaud.
Everyone arrives at the O’Briens’ for the reception, including Luke. He approaches Bree and explains that when things are going too well, he’s afraid that it will all go wrong. But she makes him want to trust, and he wants to try with her. She does too, pulling him in for a kiss.
Evan promises to deliver Abby to the afterparty, but he has a stop to make. They walk into a beautiful, perfectly furnished home on the Bay. The place is his. He’s given up his old home and wants to embrace change. They take a seat outside on the patio, overlooking the water. He explains that since he’s been in Chesapeake Shores, he’s been happy. He loves her whole family, but most of all, he loves her. He kneels and holds up a ring. “Abby O’Brien, would you be my wife?” She tearfully accepts. She’s overjoyed when she realizes there’s room in the house for her daughters, Nell when she returns from Ireland, and even Mandrake, with a private apartment above the garage (no matter who he decides to work for).
At the reception, the family gathers around the familiar firepit. They all share their warm wishes for each other, especially when Abby reveals her engagement to Evan. That news is topped only by Jess’s toast: “Things come back to where they belong. To Mom & Dad.” After a brief pause, she adds, “And I’m pregnant.”
Abby takes time to reminisce, recalling many family moments around the fire, filled with laughter, love, and tears, always together. Mick shares his own thoughts for his children and his new wife. “As I look around this circle, this group of people who mean more to me than anyone else on this planet, and I see this spectacular woman I somehow got to agree to marry me… again… that’s truly the luck of the Irish.” He raises his glass, “To family.”