John Malkovich Hercule Poirot Actor Rupert Grint Inspector Crome Actor Andrew Buchan Franklin Clarke Actor Eamon Farren Cust Actor Jack Farthing Donald Fraser Actor Tara Fitzgerald Lady Hermione Clarke Actor Shirley Henderson Rose Marbury Actor Bronwyn James Megan Barnard Actor Freya Mavor Thora Grey Actor Kevin R. McNally Inspector Japp Actor Anya Chalotra Lily Marbury Actor Lizzy McInnerny Jenny Barnard Actor Suzanne Packer Capstick Actor Michael Shaeffer Sergeant Yelland Actor Christopher Villiers Sir Carmichael Clarke Actor Tamzin Griffin Alice Asher Actor Agatha Christie Writer Sarah Phelps Writer, Executive Producer Farah Abushwesha Producer Alex Gabassi Director Basi Akpabio Executive Producer James Prichard Executive Producer Damien Timmer Executive Producer Helen Ziegler Executive Producer Elizabeth Kilgarriff Executive Producer