With all the delays the corona virus is causing, the CW is pushing the premiere of the mid season shows like Legends of tomorrow to a later date than January 2021 (source) with the synopsis being as follow, please be aware it contains spoilers from the finale of the current season that didn’t air yet:

Having spent last season trying to track down the Loom of Fate in order to bring back their slain comrades, the Legends must now save history from a foe like none they’ve encountered in the past or future. Co-captains of the time-ship Waverider Sara Lance and Ava Sharpe have dealt with monsters, time anomalies, and most recently, villains from Hell, but this season they will face something even more challenging and bizarre … space aliens!

After one of their own is abducted by a ruthless alien, this new mission becomes personal. It will take more than the combined powers of a dark magician, John Constantine; a semi-reformed arsonist, Mick Rory; historian who transforms into steel, Nate Heywood; and a brother-sister wind-totem-wielding duo, Zara Tarazi and Behrad Tarazi to save the world for a sixth time. They must recruit a new Legend, a woman who was abducted by aliens when she was a child and supposedly imbued with powers that will help the team defeat their intergalactic foes. Either that or she’s just crazy…