![Knock at the Cabin](https://image.tmdb.org/t/p/w185/dm06L9pxDOL9jNSK4Cb6y139rrG.jpg)
Based on the novel by Agatha Christie In this TV movie, a classic mystery is updated and relocated to a glamorous world of London socialites and secret agents, introducing two unique and compelling investigators and taking us through to the highest corridors of power.