Mary, still intent on her independence, finds herself buried under a number of unpaid bills after losing her job at the pool hall. Meanwhile, ""The Colonel"" (guest-star Peter Graves) surprises Eric and Annie with an unexpected visit. Matt blames everyone but himself for his failing grade in organic chemistry class. Lucy enlists Simon to assist her with her Homecoming Queen Campaign to help him gain popularity in school, and Ruthie's prayers are answered when she's transferred out of her nemesis' class and into a prestigious private school.

Mary's future may be resolved, but the rumor mill surrounding her situation runs rampant. While ugly rumors spread about Mary's sudden departure, Simon is persuaded to use his sister's bad reputation to boost his 'cool' quotient at school and gets into some trouble of his own with identical twin bad girls, Carol and Sue Murphy (Mary Kate and Ashley Olsen, Full House). Congregational gossip irks Eric. Lucy wrestles with high school hearsay. Ruthie spreads phony tales to draw attention away from Mary, and Matt's infatuated with a beautiful stranger. Also, Annie goes out with an old boyfriend.

Matt begins to go crazy over a psychological evaluation that he is required to take for his medical-school application. Matt also notices the strange demeanor of his psychologist, which leads to a surprising twist. Meanwhile, after Ruthie gets into trouble at school for missing homeroom classes daily, she tricks Robbie into coming to talk to her principal. Simon decides he no longer wants to be together with Sasha since they have nothing in common and that she is not that intelligent, but the plan backfires on Simon. Also, Mike wants to try to be in a relationship with Lucy again, but unfortunately she turns him down since they are both on the rebound from Jeremy and Elaine. Lastly, Eric must convince a terminally ill patient to embrace life no matter what the doctors tell him.

The Glenoak Community is making a big fuss over a petition that is protesting the apparently unfair firing of one of Ruthie's teachers, Mrs. Miller at her private school. Annie's father Charles drops by at the Camden's for a visit. Annie is then surprised and shocked when she she learns she has a half-sister.

As Annie begins teaching, she inadvertently gives a student some bad advice. At the same time, Eric and Annie painfully discover how much their constant arguing is affecting the family. Lucy and Robbie finally face up to their feelings after she intentionally sabotages one of his dates out of jealousy. Cheryl goes to Eric for some guidance in her relationship with Matt, but she misinterprets the reverend's input in the matter. Simon is attracted to a girl who is dating one of his friends. Mary is left to mull over Wilson's marriage proposal and it's even more confusing when she has a romantic encounter with a fellow firefighter trainee who shows an interest in her.

Annie quits her job at the private school without discussing it with Eric first and he feels completely left out. Mary tries to call Wilson and learns from his landlord that he has moved out of his apartment. Simon uses Robbie's car to practice driving and gets him in trouble when Simon smashes into Matt's car. Robbie's brother Ronald stops by at the Camden home for a visit. Mary gets an unexpected visit from Ben, the fireman she kissed. Ruthie's old teacher Ms. Riddle starts working at Ruthie's school.

After various personal items disappear from the house, the family finds Ruthie in the garage apartment entertaining a friend with the pilfered items. The would-be bandit explains that she is hiding her pal from a pair of older boys, who have been harassing the girl because of her Muslim background. Touched by her plight, Mary and Lucy try to get their neighbors to sign a petition in support of the girl's family. Matt and Simon decide on a less civic solution and go hunting for the perpetrators.

Matt stays out all night with Sarah and they secretly elope, but when facing their parents they're only able to summon the courage to say that they're engaged. A worried Annie tries to calm Eric down, who is convinced that Matt did something foolish. Meanwhile, Lucy and Mary search for Ruthie because they suspect that she knows what really happened during Matt's night out. Ruthie and Matt agree to keep the marriage a secret until a Jewish wedding in a few months.