Material Witness (2003)

The FBI suspects' fraudulent business practices are linked to the mysterious disappearance of Candor Diamond Corporation president, Irwin Margolies. Weeks after Margolies turns up, and begins cooperating with authorities, several Candor employees are now the victims of brutal murders. The deaths all point to the work of a hired hit man, with possible links to Margolies, but it will take the concentrated efforts of federal agents to untangle the web of clues to convict the killers.