'Killing Eve' star Fiona Shaw will also make a guest appearance in the hit BBC/Amazon comedy, which is returning this spring.

Kristin Scott Thomas and Fiona Shaw are set to guest star in season two of Phoebe Waller-Bridge's breakout comedy Fleabag, which will premiere on BBC Three and Amazon Prime Video this spring.

The pair join a stellar principal cast for Fleabag’s second outing, which includes returning castmembers Olivia Colman (Godmother), Sian Clifford (Claire), Bill Paterson (Dad), Brett Gelman (Martin), Jenny Rainsford (Boo), Hugh Skinner (Harry), Hugh Dennis (bank manager) and the already announced addition of Andrew Scott (The Priest).

Meanwhile, plot details of the show have emerged, with Waller-Bridge's titular character set to meet a priest who jolts her into seeing the world in a different way. Picking up a year on, there are still old wounds to unpick and new ones to dress as the next chapter of Fleabag’s life takes her to hell and back.

Fleabag and Claire are brought together by an unexpected attack and tensions rise as another side of her sister emerges. Further afield, Dad still can’t look Fleabag in the eye and Godmother slithers closer into the girls’ lives. With hope and faith at the core of season two, the heroine finds herself in the midst of a battle she is determined to win: Fleabag versus God.

"They literally begged me to be in it," said Fleabag creator and star Waller-Bridge. "Begged me. Begged. One of them was crying.”

Added Scott Thomas: “Phoebe Waller-Bridge cannot be ignored. She manages to hit core issues with sledgehammer brutality as she trips along with a spring in her step. I laughed helplessly as I binge-watched the first brilliantly funny series and enjoyed being aghast at times. I was very flattered to be asked to be in series two”

Shaw, who recently worked with Waller-Bridge on Killing Eve, said: “Phoebe's mind is like nothing else.”