Mervin reopens his mother's case and uncovers the prime suspect in her murder. But even though everything points back to this suspicious figure, they can't work out how foul play was involved. By all accounts, Dorna took a boat out in a storm of her own volition and drowned at sea. Just as the team starts making headway in the case, Sterling pulls rank and throws a spanner in the works. Can a world-weary Selwyn help them before it's too late?

And old wounds are reopened as Mervin is forced to confront his past. But will he finally get the answers he's looking for?