Jonathan Potash was an SD-6 hitman.
Jonathan and one of his partners were on a stakeout while Vaughn and Sydney were having dinner inside a restaurant. After scanning Vaughn's face through the DMV database, Jonathan and his partner found out Vaughn worked for the CIA.
The duo ambushed the couple's dinner and tried to kill them both; they fled the restaurant through the back door and into an alleyway. While escaping from Jonathan's partner, Jonathan showed up at the other end of the alley and forced them to hold up their hands and get on the ground. Jonathan called Ariana Kane and was about to inform her of the news, but Vaughn stabbed Jonathan's partner in the throat and took his machine gun, riddling Jonathan with bullets in the confusion.