A private investigator helps a former flame solve the murder of her wealthy grandfather, who lived in a sprawling estate surrounded by his idiosyncratic family.
| Writing | Agatha Christie | Novel |
| Directing | Gilles Paquet-Brenner | Director |
| Camera | Sebastian Winterø | Director of Photography |
| Sound | Hugo de Chaire | Music |
| Production | Reg Poerscout-Edgerton | Casting |
| Production | James Spring | Producer |
| Production | Lisa Wolofsky | Executive Producer |
| Art | Simon Bowles | Production Design |
| Production | Anders Erdén | Executive Producer |
| Costume & Make-Up | Colleen Kelsall | Costume Design |
| Production | Jane Hooks | Co-Producer |
| Writing | Tim Rose Price | Screenplay |
| Production | Jay Firestone | Executive Producer |
| Editing | Peter Christelis | Editor |
| Writing | Gilles Paquet-Brenner | Screenplay |
| Costume & Make-Up | Cate Hall | Makeup Designer |
| Production | Sally Wood | Producer |
| Writing | Julian Fellowes | Screenplay |
| Production | James Swarbrick | Executive Producer |
| Production | Compton Ross | Executive Producer |
| Directing | Mark Hedges | First Assistant Director |
| Production | Joseph Abrams | Producer |
| Production | Andrew Boswell | Executive Producer |
| Costume & Make-Up | Catriona Johnstone | Makeup Artist |
| Camera | Charlie Wyldeck-Flowers | Key Grip |
| Editing | Charlie Thompson | First Assistant Editor |
| Sound | Jim Barne | Orchestrator |
| Sound | Matt Davies | Dialogue Editor |
| Lighting | Andy Cole | Gaffer |
| Sound | Vincent Watts | Music Editor |
| Sound | Craig Irving | Sound Re-Recording Mixer |
| Sound | Rob Turner | Sound Effects Editor |
| Visual Effects | Chris Reynolds | Special Effects Supervisor |
| Art | Simon Lamont | Art Direction |
| Art | David Wood | Art Direction |
| Visual Effects | Kent Houston | Visual Effects Supervisor |
| Camera | Rami Bartholdy | First Assistant Camera |
| Camera | Amandine Klee | Camera Operator |
| Sound | David Lascelles | Sound Mixer |
| Sound | Paul Carter | Sound Designer |
| Art | Rebecca Gillies | Set Decoration |
| Art | Rod Whiting | Property Master |
| Camera | Nick Wall | Still Photographer |
| Sound | Tim Hollier | Music Supervisor |
| Costume & Make-Up | Sarah Nuth | Makeup Artist |
| Art | Sion Clarke | Supervising Art Director |
| Costume & Make-Up | Cate Hall | Hair Designer |
| Visual Effects | Drew Jones | Visual Effects Producer |
| Costume & Make-Up | Vidya Krishnamurthy | Key Costumer |
| Costume & Make-Up | Sarah Nuth | Hairstylist |
| Crew | Matt Fyson | Armory Coordinator |
| Crew | Paul Harris | Choreographer |
| Production | Arabella Gilbert | Production Coordinator |
| Art | Ben Gladstone | Location Scout |
| Production | Lillie Jeffrey | Casting Associate |
| Production | Emily Precious | Associate Producer |
| Production | Katy Covell | Casting Assistant |
| Art | Austin Salt-Cowell | Location Scout |
| Production | Benedict Minghella | Casting Assistant |
| Production | Tamsyn Manson | Casting Assistant |
| Writing | Julien David | Adaptation |
| Writing | Rachel Parker | Adaptation |
| Production | Inga Fabian | Production Secretary |
