When a suspected American arms dealer with a lengthy rap sheet pops up in Vienna with stolen weapons, the Fly Team sends Mitchell and Smitty undercover to try to infiltrate his operation. During the mission, Smitty enters muddy waters while working with the suspect's wife. Meanwhile, Mitchell's biological father shows up in Budapest after being released from prison to seek him out despite Mitchell's disinterest.

When an American student and sex worker is murdered in Budapest, similarities to a recent case in Japan lead the Fly Team to partner with detectives from Tokyo.