Some rules are meant to be broken. Some secrets are meant to stay buried.

On a military barracks on the outskirts of Glasgow, a vulnerable young soldier dies during a routine training exercise. The army brass is quick to rule it a tragic accident.

But DCI John Lomond is called in after a tip-off suggests foul play.

Forced to work alongside a hostile military police, Lomond and his Major Investigations Team find themselves obstructed from all sides.

Stripped of his usual authority, Lomond must navigate an unfamiliar chain of command, and a culture of silence and secrets.

To find the killer, Lomond has only once choice – convince someone on the inside to do the unthinkable: break ranks. But in a place where loyalty is the law, telling the truth might be the one thing that gets you killed.