A Puerto Rican gang leader that Mac helped put in prison many years ago is released, and suddenly the new leaders of the gang begin turning up dead.
When the leader of a powerful New York gang, El Puño, is found murdered, the CSIs must find the killer before a street war with a rival gang breaks out. Mac asks the co-founder of El Puño, Luther Devarro, a man he put behind bars years before, for help.—CBS Publicity