As the smash hit drama returns, Nurse Sarah Nordmann (Marta Dusseldorp, Jack Irish, Janet King) and the wealthy Bligh family face new challenges amid sweeping social change in 1950s Australia. Villainous Regina (Jenni Baird, The 4400) has finally ensnared Bligh patriarch and political aspirant George (Brett Climo, Snowy River: The McGregor Saga) in marriage, but she continues to plot against Sarah, exploiting the rising fear of Communism to target her rival. As Sarah teams up with formidable dowager Elizabeth (Noni Hazlehurst, Little Fish) to expose Regina, James (David Berry, Outlander) and his estranged wife, Olivia (Arianwen Parkes-Lockwood, Underbelly) forge a fragile peace, and Anna (Abby Earl, The Great Mint Swindle) strives to advance her literary career. The supremely talented cast also features Craig Hall (The Doctor Blake Mysteries), Frankie J. Holden (Something in the Air), Aldo Mignone (Danger 5), and Sara Wiseman (Mercy Peak).
Sarah steps in to help at the local school after one of the teachers dies in an apparent suicide. Carolyn and George act as mediators between James and Olivia, who are living separately and barely speaking.
Sarah confronts Regina about what really happened to Milly, but she fails to anticipate Regina's sway over Sergeant Taylor. Olivia comes clean to James about Georgie, and Anna meets with Sir Richard behind Carolyn's back.
After Sarah's dismissal from the school, Jack offers his support for Sarah, putting himself in Sergeant Taylor's crosshairs. Elizabeth is released from the hospital as Olivia returns to Ash Park.
As Inverness prepares for the prime minister's visit, George discovers what Regina has been up to with Sergeant Taylor. Elizabeth and Anna plan to sabotage Regina's dinner, while Sarah moves Harry into the hospital.
After restoring law and order to his house, George meets with Sarah and expresses his intentions. Regina moves back into the cottage, but the family worries that she may still be dangerous, and so Elizabeth meets with Sarah.
Sarah tells George that she invited Harry to stay with her and Roy, a decision that angers Elizabeth, who can't help but interfere. Elizabeth and Sarah become adversaries again over whether or not Harry should remain in Inverness.
Carolyn and Jack continue to be apprehensive about Sir Richard's threats against them, even as their wedding day approaches. Harry and Roy notice Milly's fiancé, Gordon Walsh, following Sarah and warn her that she may be in danger.
Jack and Carolyn's honeymoon is interrupted by the revelation that Sir Richard is targeting Douglas's refuge for needy veterans. As George prepares to leave for Canberra, Sarah asks the Bligh family to keep away from the birth to avoid scandal.
After a long and difficult labor, Sarah gives birth, but the baby's future remains uncertain. Carolyn tries to follow Sarah's wishes and prevent Elizabeth from telling George the news.
Elizabeth calls Anna and Gino back from Italy to set her plan against Regina in motion, but Gino disapproves of her using Rose. George and Regina return to Inverness from Canberra, unaware of the trap Elizabeth has laid.