James is on trial in chilling finale

When the body of a missing child is found along with a note reading ‘They must be destroyed”, Ronnie recognises a horrifying parallel with an old case in which he was involved. Racist Andrew Dillon was convicted six years earlier of killing three young boys of foreign descent. But with Dillon long since behind bars, who is behind this latest dreadful crime? Either a copycat killer is picking up where he left off, or there is a different explanation almost too terrifying to contemplate.

The case also rakes up the past for an increasingly twitchy James. The Senior Crown Prosecutor is under intense scrutiny once it is recalled that not only did he successfully prosecute Dillon for the killings of six years earlier, but also that his success at the time was due, in large part, to ‘selective prosecution’, potentially involving some kind of foul play against the defendant.

Sam Cain (guest star Tobias Menzies) is the formidable prosecutor brought in to challenge him. Was key evidence buried in order to win a conviction and secure a promotion? If so, it could turn out to be a career-ending mistake for James – and he might just end up bringing colleague Alesha down with him…