It’s all change at Nonnatus House – and no one’s happy about it! After their lovely South African adventure, TV’s most caring medics are back in Poplar.

But things aren’t the same, as Sister Ursula (Harriet Walter, being brilliantly chilly), who has been sitting in for Sister Julienne, is given charge of Nonnatus House for good and upsets everyone, especially a miffed-but-trying-not-to-show-it Julienne!

Meanwhile, there are some truly harrowing scenes when Sister Mary Cynthia is reminded of her terrible attack as the team help a pregnant woman and her son who are at the mercy of her violent jailbird husband.

Elsewhere, Shelagh’s got a surprising secret, but can she pluck up the courage to tell Dr Turner?