What Sarah Phelps has done with Agatha Christie’s stories has been nothing short of miraculous. When the BBC and the Agatha Christie estate announced it had signed a new deal in 2015, we weren’t quite sure what the fruits of the deal were going to taste like – more by-the-book Miss Marples and Poirots? Vanilla adaptations of some of her other stories? The fruits turned out to be something totally fantastic, and so far we’ve had two Christmas event series that have been meaty muthas, stuffed with emotion, heartbreak, tension, and extra characterisation and social context. Now we know for sure that Phelps will be back with us for a third Christie adaptation.