While undercover G realizes that someone tails him; G chases him; the tail runs into the paths of two vehicles, each of which hits him; G hears his last words: "Callen, Callen". G leaves the scene, and he sends a codeword to signal that the operation has become breached; G becomes a ghost, and he receives two weird phone calls from Eugene Keelson, who offers to sell data to G about himself in return for a favor. G accepts the offer; the OSP server becomes compromised, so Eric shuts it off; Hetty says that G is alone and in the cold; a group of armed Bulgarians approach G, who does the favor, but the deal turns sour; G torches a Burb and walks away; Sam finds G and chats him up; on a borrowed server Eric gets a trace on the Bulgarians; Sam makes a discreet inquiry; another meet and shoot-out follow. Hetty tells G that the entire NCIS has become compromised, and she brings him back in from the cold; G meets Keelson and zaps him. Eric gives the gang another lead.