Malcolm Fox and his team are back, investigating whether fellow cops covered up for Detective Paul Carter. Carter has been found guilty of misconduct, but what should be a simple job is soon complicated by a brutal murder and a weapon that should not even exist.

A trail of revelations leads Fox back to 1985, a year of desperate unrest when letter-bombs and poisonous spores were sent to government offices and kidnappings and murders were plotted. But while the body count rises the clock starts ticking and a dramatic turn of events sees Fox in mortal danger.