It's been a year since the Walker family was torn apart by a tragic car accident, and in a very un-Walker like fashion, everyone has been avoiding everyone else. Truths and reality only start to set in when the family is forced to come together for Justin's homecoming party: Nora tries to prepare for the party, but is not acting like the mother she used to be; Sarah is consumed with the Narrow Lake deal; Kevin has a new career as public defense attorney; Saul and Scotty are running their restaurant; and Kitty's life has become a taboo subject for everyone.

The Walkers attend a swanky launch party for Luc’s underwear advertising campaign where 14-year-old Paige falls in with the wrong crowd; despite several visits from Justin, Holly still struggles to remember the things that were once most important to her; Kevin is saddled with a runaway juvenile delinquent; and just as Nora very publicly admits that she’s taken a part-time job as a florist, she’s approached by a radio show producer with a job offer.

Kitty continues her stay in Ojai, trying to reinvent herself, when she meets a handsomely rugged handyman, Jack. As Kitty fakes her persona to seem like a local, she winds up in a situation that proves that honesty usually is the best policy. Meanwhile, the rest of the Walkers are in on a little surprise birthday celebration for Sarah; what they all don't know is that Sarah has been lying to Luc about her age to appear younger... It's hard to keep up with the truth.

Justin and Rebecca reach an impasse in their relationship; Holly has a breakdown over her inability to remember her own daughter; Sarah struggles to keep up with the Joneses when Cooper lands the lead role in "Romeo & Juliet"; Saul takes a huge risk to make a romantic connection with a dear friend; and Kitty struggles with an affair of the heart.

Justin suddenly takes a much more keen interest in Holly's recovery after a nurse (guest starring Odette Yustman as Annie) at the hospital catches his eye; Nora's fellow radio host, psychiatrist Dr. Karl, finds his way into Nora's heart when he helps Sarah and Kitty resolve some old sisterly squabbles; and Paige helps Kevin and Scotty find forgiveness.

The relationship between Justin and Annie gets more serious as he brings her to a family dinner. Nora has doubts about him being ready for a serious relationship since he just broke up with Rebecca.

In this 99th episode the family looks back to the events who made them who they are now. Tommy returns with surprising news, while his siblings all have to make very difficult choices. Kitty needs a break from her Life.

Nora and Sarah fly out to Washington DC to "surprise" Evan for his birthday, but what they're really after is the truth behind Kitty's extended trip to the east coast. Meanwhile, Kevin and Scotty are thrilled to have officially signed the papers to be Olivia's parents, but the excitement quickly fades when Olivia seems a little nervous about moving in and starting a new life.

When Olivia's brother shows up and sets out to gain custody of her from Kevin and Scotty, the Walkers struggle amongst themselves to determine what's best for Olivia.

As Sarah and Luc’s nuptials approach, plans go horribly awry and the Walkers learn several surprising lessons about the real meaning of family, on the Series Finale of “Brothers & Sisters”.