Undercover Assignment to Stop Serial Killer/Former Marine Staff Sergeant Andrew Hoffman is an undercover operation that occurred in May 2008 when the main NCIS Major Case Response Team investigated the killings of various Marine wives with NCIS/Mossad Liaison Officer Ziva David going undercover as Gina (alias) who later became Hoffman's girlfriend. The assignment later resulted in the Confrontation Between Ziva and Andrew Hoffman.