Dame Agatha Christie left behind some of the greatest murder mysteries of all time, and for her family, it amounts to a lot more – these whodunits are racking up tens of millions in profit.

It’s been 50 years since Christie died, aged 85, but the world has been following the queen of crime’s lead ever since, with film and TV producers getting their fingerprints all over her novels by adapting them into hit projects.

Netflix recently found success with the 2026 limited series Agatha Christie's Seven Dials, and Kenneth Branagh played the moustachioed sleuth Hercule Poirot in three high-profile film adaptations from 2017 to 2023.

Other Christie adaptations to have recently aired include Tommy & Tuppence, as well as Towards Zero, with a new Miss Marple audio series, in which Toni Collette will voice the consulting amateur detective, set to be released in August. A new Marple novel, written by Lucy Foley, was submitted to the company in 2025.

The increased interest in Christie’s works has seen revenue for Agatha Christie Limited, run by the writer’s great-grandson James Prichard, rise from £22.7m in 2024 to £33m. Documents on Companies House note this has been “primarily driven by increases to publishing, TV distribution and licensing revenues” – and states it is “actively looking at opportunities for growth in all categories”.

Also aiding with the revenue is the enduring interest in shows based on Poirot and Marple – starring David Suchet and Geraldine McEwan – that were originally broadcast between 1989 and 2013.

The documents said that this “demonstrated consistent customer appetite for evergreen Agatha Christie adaptations as well as for the newer content”.

Ownership of the company, founded by the author in 1955, is split between Christie’s family and RLJ Entertainment, a film company based in the US.

“New TV productions and feature films are important to the group not only because of the revenue generated directly through licence fees, broadcast fees and distribution income, but also because of the indirect impact on other areas of the business such as publishing,” the company added.

Born in Torquay in 1890, Dame Agatha penned 80 crime novels and more than 25 plays, including The Mousetrap. Her works have sold some two billion books, with over one billion in the English language alone, according to her website.

A new exhibition celebrating Christie’s life will open at the British Library in October, showcasing personal items, many of which have never been publicly displayed, including her typewriter.

Prichard said of the exhibition: "My father, Mathew, has carefully selected a wide range of items from the Christie Archive which offer remarkable insights into Agatha Christie from both a professional and personal perspective, and that are sure to fascinate visitors.

“It feels fitting to do this to help mark the 50th anniversary of her death; this combines an opportunity for quiet reflection, but also an opportunity to celebrate the immense achievements of her life. Hers was truly one of the most remarkable lives of the 20th century."