Mark Sadowski is an inspector for the International Atomic Energy Agency and also the boss of Lieutenant Roy Sanders, Diane Russio and Holly Stegman. At some point, after an interrogation by Special Agent Leroy Jethro Gibbs into the circumstances surrounding Sanders's radiation poisoning, Sadowski fell ill and was treated by Doctor Donald Mallard before Sadowski was transported to Armed Forces Institute of Pathology and then sedated. It's not known if Sadowski survived his poisoning or if like Lt. Sanders, he eventually succumbed to the illness, dying from it.