The Serpent

BBC1, 9pm

Those two million of us (apparently) who have been strong willed and old fashioned in waiting for this true-life drama to be broadcast each week can now see the final chapter of the quest to bring Charles Sobhraj (Tahar Rahim) and Marie-Andrée Leclerc (Jenna Coleman, right) to justice.

How soon can they be stopped before they claim more victims from among the unsuspecting hippies who cross their path on the exotic tourism trail of the mid1970s? Having fled to India, the two of them have found more prey to fund their planned escape to South America – but remaining free with an international arrest warrant out for them is proving to be an increasingly unlikely outcome.

The superb quality of storytelling and acting – especially Rahim’s chilling credibility – remains undiminished right up until the end.