It's 1933, and an older and greyer Hercule Poirot receives letters threatening murder. When no-one listens to his appeals, the once great detective must take matters into his own hands.
Guest Stars:
Neil Hurst, Kevin McNally, Tamzin Griffin
The ABC killer sends more letters promising to spill blood. Hercule's past, integrity and identity come into question while he fights a rising tide of xenophobia.
Guest Stars:
Gregor Fisher, Cyril Nri, Lorenzo Harani, Ash Matthews