A computer printout letter from the grave was delivered anonymously to New York City&#39;s&nbsp;<b>top cop</b>&nbsp;inside his 25th division precinct station house office in Brooklyn. It contained details to a diabolical plan of hate and revenge targeted against the cop in question, who put this&nbsp;<b>master criminal</b>&nbsp;in the grave.<br /><br />The letter contained details to a hideous plan of mass murder which took years to finalise.<br /><br />The police had to uncover the identity of this mysterious mass murderer in order to begin the hunt to locate him - and save everyone&#39;s lives in New York at risk of being targeted for murder and death.