The Camden family gather together for Matt and Sarah's wedding. Eric and the Rabbi make amends while Ben and Kevin decide to go to Glen Oak to pursue Mary and Lucy. Ruthie and Simon sort out their issues with Robbie.

Matt discusses wedding plans with Eric and his future father-in-law, Rabbi Glass. Matt makes a spontaneous decision that infuriates his father and creates tension between the two families. As all this is going on, Annie tries to plan the perfect rehearsal dinner, but she is having some difficulties. Annie's father and stepmother are flying in for a visit, but they get lost at the airport. Simon is angry when Matt does not choose him to be his best man, and Ruthie gets into an unexpected fight with Robbie. Finally, as Aunt Julie goes into labor, Lucy argues with her boyfriend over moving arrangements.

Annie discovers Ruthie is writing to a Marine fighting in Afghanistan as part of a school project. The Camden family read what Ruthie has written to her pen pal about their lives and in turn learn about a Marine who so bravely has left his wife and son to fight in the war against terror. When Ruthie fails to get a response email at school and Eric hears about a helicopter going down killing two people he contacts the Colonel.

The Camden home is surprised, especially Eric, by the arrival of Mary with her lover Ben, his brother cop Kevin, now Lucy's, and her new job as flight attendant which enabled their cheap flights. Still obsessed with Matt's secret, hopefully marriage, which Robbie and Ruthie help keep, Eric neglect his counseling appointment with the elderly Tallridges couple about their adult son Jerry's 'sudden' moving out, yet just that will inspire him.

Matt and Sarah argue over their wedding plans and their agreement to forgo buying an engagement ring, and seek Eric for advice—who is not happy with Matt for getting engaged in the first place. Through the advice of Eric, Matt buys Sarah a fake engagement ring. Mary and Lucy fly to Buffalo for a weekend, or at least that is what Lucy thinks, as Mary makes plans of her own. While there, Lucy meets a police officer named Kevin who confiscated her bag, and he invites Lucy and Mary to a double-date with him and his brother—but with a big surprise in store for Mary.

Annie frantically cooks Jewish dishes as the Camdens prepare to head out to a Shabbat dinner at the Glasses. Simon asks Matt and Sarah if he can bring his friend Morris to the dinner. Matt agrees to allow Morris to come to the dinner as he is half-Jew. That, however, does not go as he planned, as he is not very knowledgeable about his faith. Lucy and Mary play sick to try to skip the outing so they can stay home with Robbie. While home, Mary flirts with Robbie. Lastly, Eric and Annie are unable to handle it all when they are shocked to find out during dinner that Matt is considering to convert to Judaism.

After a love night, Matt has got married with rabbi Glass's daughter Sarah. Robbie is mildly amused at the fuzz of all other Camdens speculating and worrying whether Matt 'was dumber than Mary with Wilson'. Only Ruthie finds out, answering when Matt calls, but is sworn to secrecy. Meanwhile Matt and Sarah go tell her parents first, but she shies away from telling the truth and pretends they just got engaged, a lie they now have to extend to the Camden home, where the 'news' only adds to the mounting stress.

Robbie's apparently firm happiness with Joy causes envy with his roommate. Matt is now in love with wedding plans, enough to vow his next steady date must be for keeps. Matt misses his date with a promising candidate, being commandeered for clinic duty. Yet thus he meets a fellow med student, Rabbi Richard Glass's daughter Sarah, who get doc's blessing. She insists they must meet each-other's families. Although both parents pairs plead against a mixed religions couple, the love-birds soldier on.

Valentine's Day delivers a few surprises for the Camden family as a grounded Simon is asked out by a senior, named Maria. Annie's attempt to surprise Eric with romantic Valentine's plans backfires, and results in a big fight. Meanwhile, a nosy Mary discovers Robbie's plans with Joy. Lucy runs into her ex-fiance Jeremy outside one of her classrooms and finds out that he is going to the pool hall to meet with a "friend" for Valentine's, which is to Lucy's surprise. Mary also meets up with Wilson who also has a new girlfriend, her old friend, Corey Conway. Also, Matt seeks his fathers help with his love life, and wants to get serious with a girl—which leads him to seek out old girlfriends as to why they are no longer together. Lastly, Ruthie is hesitant to go to a party because her friend tricked her into asking out a boy that she is already going out with.

With Robbie still in Florida, Matt fails to warn Simon, who got paternal permission behind ma's back, for the angers of attending older boys' parties. Simon's mate Morris drives him home but hesitates to ring given spiked punch promises a killer hangover anyway. Meanwhile Lucy settles her mutual good/popular girl jealousy with Mary, but jointly attending a frat party nearly sees Lucy forced to drink.

While Robbie visits his mother in Florida, Ruthie sneaks in her friend Yasmine Halawi, a Muslim girl who became the target of two bullies on the street. All Camdens feel obliged to help the Halawi family, which lived in Glenoak for years without problems, but every attempt proves hard or even counterproductive. Matt and Simon nearly beat up wrong suspects. Ruthie's private school's board votes against admitting Yasmine.

Annie quits her teaching job without discussing it with Eric first; and Mary calls Wilson and learns from his landlord that he has moved out of his apartment. Meanwhile, Simon uses Robbie's car to practice driving and he accidentally smashes into Matt's vehicle and this finally prompts Robbie to confront Matt about his relationship with the Camdens.

Simon's big day, the start of his driving lessons, finally arrived, but Eric just forgot about it. Grandpa Jackson seduces the knave into driving him around without a license, which leads through more bad grandfatherly advice to a televised police car chase. Jealous of Joy, Matt behaves childishly toward Robbie whose gentleman's attitude ultimately gives in. Lucy hoped Jeremy called to make up, but he just wants his engagement ring back. The local fire chief isn't fooled by Mary's eagerness to transfer.

Mary and Lucy ask their parents to find new boyfriends (and potential husbands) for both of them. Robbie argues with Joy about spending so much time together when she insists on seeing him right away. Meanwhile, Simon and Matt use the twins to attract women.

Robbie is happy with his new hot Latina girlfriend Joy Reyes and persuades her rich, devoutly Catholic father Ramon Reyes (for now) of his honorable intentions. The garage apartment squatters' resolve is self-sabotaged by their rivalry to get what shouldn't be Mary's and Ruthie's scheming. In the end return under the maternal yoke and make up (more or less forcibly) with Mary, who meanwhile repents, but Eric wisely doubts her sincerity and rectitude.

The Camden house gets a little more crowded when Mary returns, and tells her family that she is home to stay. Mary's sudden arrival has everyone in the family wondering what happened between her and Wilson. Are they married? Did they break up? Only Mary knows and she is not telling—at least not yet. Her presence delights Annie, who goes out of her way to make her daughter comfortable, even offering her the coveted garage apartment. But not everyone is happy to see her. Ruthie feels that Mary owes everyone an apology for the actions that led to her initial ouster from the Camden home.

Simon meets up with an old girlfriend, Sasha and they both try to catch up on their personal lives. Lucy and Robbie argue over who should tell Mary about their emerging relationship. Matt worries that a young woman in his study group might be a victim of physical abuse at the hands of her belligerent boyfriend. Elsewhere, Eric's sister shows up at the house with her toddler and annoys Annie as she tries to prepare a lesson for her class.

Robbie is insecure, hiding his budding rebound-affair with Lucy. Wilson is deeply hurt when he finds fickle 'bride' Mary kissing fire department course mate Ben Kinkirk. Simon doesn't enjoy bully-mate Rick's girl abusing him as excuse to dump him. Annie experiences her flippant advice nearly wrecked pupil Christy Parks's parents' marriage, yet resists help even from Eric.

Eric tries to arrange a romantic evening alone with Annie, but she rebukes his every attempt. Meanwhile, Simon's tardiness and poor people skills put his new job in jeopardy. Robbie sets Lucy up on a date with one of his friends. And Matt is concerned about a woman who keeps showing up at the clinic.

Robbie offers to pay $200 rent for the garage apartment if it ever gets finished. However the siblings all want it, so Matt is promised a switch with his room and the others whine jealously. Billy clearly pretends to be 'really' sick to make Mary stay with him and perhaps become his first mama. Lucy promised handyman Ray Rickey work on the garage apartment, but the crook fakes a fall and has a leech-lawyer waiting.

Simon stands up for a bullied student only to have the boy tell him that he is going to shoot his tormentors. Robbie gives Ruthie a playful nickname and she comes up with a less-pleasant one for Lucy. Meanwhile Lucy snaps at Ruthie, and teases her before bed about being called snooki, and it comes back to haunt her when she unwittingly ends up causing a rift in Ruthie and Robbie's relationship. Eric gets a visit from an old female friend with family issues of her own.

Eric's stress level rises when he learns that Matt has lost his job at the hospital, and is relying on his pals to find him new work. Simon adds to the tension by pressuring his pop to let him get his learner's permit. Lucy just cries in her room and refuses to discuss what happened in New York between her and Jeremy. Even lodger Robbie, still longing for Mary, is moping around the house. To top it all off, Annie's odd behavior has Eric wondering what is going on with her.