Oliver, John, Laurel, and Tatsu seek out an important person within the Monitor's plan. Connor has a heart to heart with his brother.

Reunited with his sister, Oliver and Thea find themselves searching through a familiar maze of catacombs. Meanwhile, John and Lyla partner on a special ops mission.

Upon learning the key to oppose The Monitor, Oliver and team return to Russia on a mission to gather the necessary materials. Connor reunites with a figure from his past.

After being double-crossed by Lyla, Oliver finds himself facing a life or death situation that seems very familiar. Laurel has the opportunity to make amends with the past.

Oliver's mission takes him to Lian Yu where he tries to ignore the repercussions of the looming Crisis until he receives help from an old friend. Meanwhile, a united Team Arrow faces a recognisable villain.