Rescued from Lian Yu, Oliver makes his return to Starling City on a parallel Earth -- where events have played out very differently without him. While Oliver seeks to accomplish a mission from The Monitor, in 2040 Mia and William's team goes up against the new Deathstroke Gang.
Oliver, John, and Laurel are redirected by the Monitor to find a biophysicist in Hong Kong. In the future the team attempts to intercept J.J. and the Deathstroke Gang, and Connor has a heart-to-heart with his brother.
Oliver is reunited with Thea when he travels to Nanda Parbat to try and learn more about the Monitor, putting him in the middle of a feud between former League of Assassins members. John and Lyla partner on a special ops mission.
Team Arrow tries to cope with the sudden arrival of their own children from the future. When the Deathstroke Gang also makes a surprise appearance in a bombing, Mia and her team take it upon themselves to stop their future foe.
Oliver takes Mia and Will to Russia to track down the resources they will need for the coming crisis, putting them under the fist of the Bratva. Meanwhile, John recruits Roy to help him steal something.
After he and the team are double-crossed by an ally, Oliver finds himself trapped in an alternate reality time loop where killers are trying to take down Mayor Quentin Lance.
A.R.G.U.S. brings Team Arrow to Lian Yu to build a weapon that will be needed for the coming crisis -- but their plans are disrupted by a string of familiar faces after Dinah, Roy, and Rene's plane is shot down.
The only surviving heroes find themselves trapped at the Vanishing Point, until Oliver Queen shows up with a last-ditch plan to stop the Anti-Monitor. As Supergirl leads a team to Mar Novu's home planet, Barry finds himself leaping through the past from moment to moment inside the speed force.
In the year 2040 Laurel and Dinah search for a kidnapped socialite, leading them to try and recruit Mia Queen -- who is enjoying a seemingly perfect life in the new reality.
After the birth of a brand new universe, Oliver Queen's loved ones grieve a profound loss. But matters are complicated when young William is kidnapped, and Mia comes to terms with her father's legacy.