Bill Nighy Leo Argyll Actor Anna Chancellor Rachel Argyll Actor Anthony Boyle Jack Argyll Actor Crystal Clarke Tina Argyll Actor Ella Purnell Hester Argyll Actor Christian Cooke Mickey Argyll Actor Eleanor Tomlinson Mary Durrant Actor Matthew Goode Philip Durrant Actor Morven Christie Kirsten Lindstrom Actor Alice Eve Gwenda Vaughan Actor Luke Treadaway Dr Arthur Calgary Actor Brian McCardie Bellamy Gould Actor Frances Grey Lydia Gould Actor Luke Murray Young Jack Actor Hayden Robertson Young Hester Actor Catriona McNicoll Young Mary Actor Abigail Conteh Young Tina Actor Rhys Lambert Young Mickey Actor Agatha Christie Writer Sarah Phelps Writer, Executive Producer Sandra Goldbacher Director Basi Akpabio Executive Producer Damien Timmer Executive Producer James Prichard Executive Producer Karen Thrussell Executive Producer Gaynor Holmes Executive Producer Helen Ziegler Executive Producer Roopesh Parekh Producer