As A.B.C. dominates the news, the public are demanding answers, fearing for their lives. Without any warning, the A.B.C. murderer strikes again in the bathroom of Embsay station, where Ernie Edwards is murdered.
Hercule (John Malkovich) and Crome (Rupert Grint) arrive at the crime scene, once again too late. However, the police have found someone’s belongings nearby and they finally sense they have got the killer in their sights.
An arrest is finally made and the country celebrates and breathes a collective sigh of relief… but something doesn’t feel right to Hercule. Have they really caught the A.B.C. killer?
A flashback to Belgium 1914 and Hercule’s true past is revealed. He’s witnessed horror like he’ll never experience again and it shapes the man he eventually becomes, explaining his life-long debt to the dead.
With a suspect in police custody and the public supposedly safe, Hercule is yet to be convinced that everything is as it seems. One piece of the puzzle remains to be solved, and it’s up to Hercule and his little grey cells to do what he does best.
Can he fulfil his life-long debt to the dead, solve the mystery and learn the true identity of the A.B.C killer?
Airdate: Friday 28 December 2018 from 9.00pm-10.00pm on BBC ONE
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