Nonnatus House suffers its biggest threat yet. But this time it’s not the bricks and mortar that are in danger, it’s the people.

As Philip leaves for a long tour, Elizabeth makes an upsetting discovery. Prime Minister Eden wants to strike back after Egypt seizes the Suez Canal.

Palace insiders try to prevent a scandal that could reflect poorly on Philip. Eden faces censure from his cabinet and the press.

Margaret and Peter come to Elizabeth with a request. With a royal scandal about to break in the newspapers, the Queen Mother intervenes.

Elizabeth and Philip go on an exhausting world journey. Margaret takes over some of her sister’s official duties and tries to liven things up.

Claire is taken to meet the Laird. As suspicions about her grow, Claire befriends the mysterious Geillis Duncan. When the clan discover her medical skills, Claire goes from guest to…