An armed robbery takes place at a Supermarket which results in the unintentional death of a security guard. Only one member of the gang who carried out the robbery stands trial for both the robbery and the murder of the guard.
At the subsequent trial he is found not guilty on both charges due to two crooked jury members. Some months later the gang carry out another robbery this time on a jewellers shop. An innocent member of the public tragically dies; once again the death is unintentional. One by one the members of the gang who carried out the robberies are murdered, by whom or why it isn’t known. Because of forensic evidence found at each of the crime scenes the Police are able to arrest a man who is subsequently found guilty of all four murders and sentenced to life imprisonment despite pleading his innocence.
The Detective leading the investigation is promoted as a result of the outcome of the case. Sometime after the court case the Detective receives an anonymous letter claiming responsibility for the four murders. The contents of the letter make it clear that this person has to be the actual killer. Who is the killer and why did they carry out the murders. The Detective now faces somewhat of a dilemma.
Does he tell his bosses about this new evidence so that the convicted man can be released and enquiries be made to discover the identity of the real killer or does he keep quiet, enjoy his promotion in the knowledge that although innocent of these crimes he is guilty of two other murders which he escaped going to prison for.