A burning fishing boat found on the Channel turns into a new case for Karl and Elise in the third and final chapter of the series.

A shocking discovery is made at an immigration removal centre alongside a sinister animation containing a hidden message.

The investigation steps up when Winnie is sent a live rat in a box, with a set of co-ordinates leading to the Pied Piper's latest victim.

As a young mother-to-be helps with their enquiries, a new development threatens to tear Karl and Elise's partnership apart.

Karl makes a foreboding discovery at Elise's apartment, and the pattern of missing people continues.

Karl and Elise face a tense and gripping showdown with the Pied Piper, while the truth about the Moreau abduction is revealed at last.