Knight to King Seven

A young architect requests a personal day to arrange a payment plan to cover the expenses of his late mother's cancer treatment. He goes through seven levels of corporate management making his request and is denied by all of them. He is told that he must report to work the next day-September 11, 2001.
He, along with 2752 other souls perished when the twin towers of the World Trade Center fell in the worst terrorist attack on American soil in history.
But the seven people who doomed him to death ranging from a design team leader to the CEO of the architectural corporation were away that day on a business junket in Las Vegas.
Now, the brother of the young man seeks revenge. Using as a calling card the image of a chess piece knight to commemorate his younger brother's reputation as a nationally famous player, he systematically aims to hunt down those individuals who he holds responsible for his brother's death.
Because the image is of a knight, Inspector Mag Goldman of the NYPD calls upon his friend and expert in all things Medieval, Professor Bradley Davison of Queens College to help track down the killer. Dr. Davison had assisted the police in solving eight previous serial killings.
But in this most challenging case, could he once again use his formidable expertise to bring a serial killer to justice?