Mark McCluskey was a secondary antagonist from The Godfather novel and movie.A Captain in the New York Police Department, he was a corrupt officer who was also working for the Tattaglia crime family, mainly with associate Virgil Sollozzo. When Sollozzo and the Tattaglia's wanted to assassinate the wounded Vito Corleone in the hospital McCluskey arrested all the men guarding Don Vito. Fortunately for Vito his son Michael Corleonecame by to visit his father and realized there was a problem. He moved his father into another room and stood guard outside the hospital, scaring off Sollozzo's men.McCluskey soon arrived and when questioned by Michael he responded by punching Michael in the face, breaking his jaw in the process. Tom Hagen soon arrived with private detectives licensed to have weapons and warned McCluskey that if he further interfered he'd have to appear before a judge and show cause. McCluskey left in a huff, realizing he had been beat.A few days later Michael met with Sollozzo and McCluskey, ostensibly to work out a peace deal between the two families. Retrieving a gun that had been planted at the restaurant by Peter Clemenza's men beforehand, Michael killed both Sollozzo and McCluskey.Following the killing of the two men Michael fled to Sicily. The police really cracked on the Corleone Family. However journalists in the Corleone payroll put out stories exposing McCluskey's mob ties, making it appear that McCluskey was betrayed and murdered by his mob allies. This helped blunt the police crackdown against the Corleone family.