In the Season 4 premiere, the ladies learn the identity of the baby who was left on their doorstep. Meanwhile, Melanie gets a job offer from a public-relations firm; and Elka tries to regain the upper hand with Pierre.
Melanie is put in an awkward situation with a coworker by her boss; Joy worries about fitting in at college; Victoria is unnerved by her director's request to change her appearance; Elka keeps a secret.
Melanie finds herself tangled up in a love triangle at the office; Joy's firefighter fantasy may be ruined by something she learns about Sean; Victoria's relationship with a movie star makes her feel insecure; Elka and Mamie have a brush with the law.
Wilbur's christening brings Joy's new family members together for the first time, but Owen is encouraged to pretend to be someone else. Meanwhile, Elka displays her artistic side by altering a church fresco; and Melanie is fed up with Victoria's obsession with her boyfriend and costar, Emmet.
Victoria's movie wraps up filming, but it leaves her wondering if she and Emmet have a future. Meanwhile, Melanie ponders her relationship with Alec; and Joy discovers a new mystery about Elka during her internship.
Victoria goes home for a visit after being tricked by her sister, but is surprised to find their mother in a disturbing state. Meanwhile, Joy and Melanie get nostalgic for the 1970s; and Elka has advice for Victoria's mother.
Elka and Mamie write jokes for a roast at the senior center; Victoria tests a new product for the Mrs. Ladypants line; Joy deals with strange family matters; Melanie gets an engagement ring in an unexpected fashion.
Victoria contacts her ex-husbands to assess their relationships when she's stuck in the hospital on the day of her bachelorette party. Meanwhile, Joy and Melanie are obsessed with a man in a coma; and Elka and Mamie bring a little bit of Las Vegas to Cleveland.
Elka and Mamie's bowling team gets back together. Meanwhile, Joy dates a professor; Victoria goes out with a director; and Melanie has a fling with a surgeon. Mary Tyler Moore, Valerie Harper and Cloris Leachman guest star.
In the Season 4 finale, the wedding day for Victoria and an imprisoned Emmet finally arrives, an occasion that brings Joy face-to-face with her son's father for the first time in more than three decades.