Reagan and Chris share an awkward dinner with Terry and Gene who are celebrating their wedding anniversary. During the dinner, Reagan's wedding ring falls off her finger; she had it sized up to fit her swollen pregnancy hand and now needs to have it sized down since she lost the weight. Terry is shocked by the amount of bling Chris bought for Reagan, but Chris tells them the ring is actually one of his grandmother's prized diamond earrings. "Gammy, that woman HATES me," Reagan throws at Chris. "She offered me 250 dollars to walk away from you on our wedding day."
"A woman proposing, how modern," a conservative Gene says as he learns that it was actually Reagan who proposed to Chris. In a flashback to eight years ago, we see a drunk Reagan surprising a mustached Chris with her proposal as "Total Eclipse of the Heart" echoes in the background. "It was everything I hoped it would be," Chris lies to Terry and Gene before we flashback to the proposal from his perspective. We find Chris and his mustache nervously practicing his proposal with the bartender. Then with the engagement ring in his hand, Chris cues Reagan's favorite song to start playing and seconds before the words escape his lips, Reagan beats him to the punch. It's like a kick to the gut as Reagan spontaneously asks Chris to marry her, but Chris plays along and accepts Reagan's proposal.
Reagan franticly searches the house for her wedding ring before Chris finds out she lost it. As she searches the couch, Chris is on the phone with a distraught Ava who begs Chris to come over and check out a troublesome noise she heard outside. Ever since Kevin left Ava, Chris has become the de facto boyfriend having to come to Ava's aid to fix things and kill menacing looking bugs. Reagan quickly tells Chris he should go help Ava as a way to get him to leave so she can search the house for the wedding ring without him knowing.
Chris arrives at Ava's house only to find out the crisis was solved; the disembodied arm she saw turned out to be a foam pool noodle. Chris turns to leave, but Ava begs him to stay. There are strange bugs in her house and the wobbly ceiling fan above her bed needs fixing. The next morning, Chris awakens on Ava's couch from a restless night of protecting her from all the strange noises in her house. He storms into Ava's room telling her he can't be her go-to guy anymore only to find her naked. "Let's just make it even so we can move past it. Please disrobe and present," a bashful Ava tells Chris. He then notices that Ava has been nesting in a pile of her ex-boyfriend's clothes; her life has really turned into a mess since Kevin left.
Reagan spends the day retracing her steps looking for the ring. "I am the worst wife ever!" Reagan says as she freaks out in front of Ava. "I retraced my steps. I went to the ball pit, the hemorrhoid cream isle, the discount panty bin... oh my god what's happened to my life?" Suddenly Julian walks in; he has replaced Chris as the de facto man in Ava's life. Reagan realizes she needs to visit Chris' grandmother to get the second earing and make a new ring. "Gammy does not like you," Ava tells her. "She offered me 250 bucks to seduce Chris away from you at your wedding."
Chris suddenly arrives with a surprise for Ava in tow - Kevin! He knew Ava was feeling down about Kevin leaving, so he brought him back from Idaho to reunite them. Kevin apologizes to Ava for the way he left, but she's all he's been able to think about. "Get out," Ava quickly tells Kevin. "I'm over you." A devastated Kevin apologizes and quickly walks away. "I've always been a strong independent woman," Ava tells Reagan, "but with Kevin I was this helpless love blob." She asks Reagan how she knew Chris was the one to marry, to which Reagan quickly replies, "No one gets me like he does."
Reagan and Ava visit Chris' grandmother to hopefully convince Gammy to give up her second earring, but Reagan is welcomed with a barrage of insults instead of comfort. Gammy shows Reagan that she is wearing the earring and in no way giving it to her; "I'm keeping it warm for Chris' second wife." Suddenly Gammy falls asleep, and Reagan uses the opportunity to try to steal the earing. As Reagan tries to pluck it off Gammy's ear, she suddenly wakes up and grabs it back. However, she is so touched that Reagan would try to steal the earring from a sleeping grandmother that she decides to give it to her... for the price of 250 dollars.
Chris finds a drunken Kevin country line dancing at a bar. He apologizes for bringing him back to Ava, but Kevin says it's really his own fault. He left so suddenly that he understands Ava's resentment. Suddenly, Julian walks in and demands that Kevin go back to Ava. "Ava loves you. Stop being a bitch!" He tells Kevin to rewrite history and show Ava that he will never leave her again. Kevin suddenly decides that he will propose to Ava, to which Julian squeals in excitement, "You marry her and I'll be her side piece!"
Chris is so inspired by Kevin's idea to propose to Ava that he decides to re-propose to Reagan. She thought she lost her wedding ring but he had it reset with an extra stone in honor of Amy. "This will be the exact kind of proposal I wanted eight years ago!" Chris screams with excitement. At The Ava Show, Reagan gets the wedding ring made from Gammy's second earing and is excited that Chris will never know the difference. Suddenly Chris calls her and says to meet him at Rowans Pub, their special engagement place from eight years ago. Reagan is ecstatic; she can show Chris the new ring and then romantically re-propose to him.
Ava meets with Kevin at her house when he surprises her with a ring. "Whoah!" Ava screams as she downs two full glasses of wine. Then she suddenly runs upstairs, refusing to get engaged while she's in her cozy clothes. Minutes later she comes downstairs dressed in formal attire. Kevin gets back on one knee and starts his proposal again until they both realize that marriage may not be best for them at this stage of their relationship. They have no song, Ava realizes, as Kevin likes Metallica and Ava has no idea what that is. "I actually feel kinda relieved," Kevin says as they both agree to table marriage for later and just enjoy their relationship as it progresses.
Reagan and Chris are at the bar, both hands on the wedding rings prepared to propose to each other. Soon "Total Eclipse of the Heart" starts playing and as they both start multi-proposing, Reagan realizes what Chris is doing and quickly stops her proposal. Suddenly a flash mob forms around Reagan serenading her with the Bonnie Taylor song. As the song crescendos to the chorus, all the flash mob's voices disappear leaving only Chris' off-key voice finishing the song. Reagan is in tears as Chris shows her the adjusted wedding ring with Amy's birthstone. "Eight years ago, I didn't think it could get any better than just the two of us, but now it is." A love-sworn Reagan quickly grabs hold of Chris and never lets go.
Reagan, Chris, Ava and Kevin wildly celebrate and dance at a bar with shot after shot until Reagan and Chris suddenly find themselves waking up the next morning in their bed. They are extremely hungover but realize Amy did not wake them up by crying. They walk into Amy's room and find her quietly standing in her crib. "She let us sleep in," Reagan says with excitement. As they try to walk back to bed, Amy calls out for them to play with her. Fighting through the pain, Reagan and Chris happily pick up a smiling Amy and play together as one loving family.