As Danny and Lexi finish tracking down the last of Farouk's black market antiquities, they begin to make plans for their future. But their plans are derailed when the Vatican is attacked by terrorists. A person from Danny's past returns, leading them on a new hunt to recover one of the greatest lost treasures of Asia, the Spirit Banner of Genghis Khan.

A visit with Simon in prison yields new information on the Spirit Banner's last whereabouts, sending the team to Russia.