Jack and the team search for a New York businessman, who disappears after he checks in for a routine airline flight home.
Kitty Walker returns home to California after having been estranged from her mother for three years, and William Walker brings Sarah into the family business.
Kitty finds herself torn between two men, Justin's new job is more than he bargained for, and Sarah and Joe face their greatest challenge yet as parents.
Justin is shaken to the core and his resolve to stay clean is weakened by a disturbing letter that could dramatically alter his future.
The Walker family airs its dirty laundry in Justin's rehab group therapy session, and Kitty considers a tantalising proposition from Senator McCallister.