Vertigo returned with a new a strain of his patented fear drug as Oliver and Laurel clashed over Laurel donning Sara's costume.
Flash and the team set out on the hunt for Ronnie as General Eiling returned to Central City. Meanwhile, Joe asked Cisco to help investigate Nora's murder.
Caitlin and Barry tried to move on from their lost relationships while a new metahuman tried to break her beau out of prison.
Diggle and Roy aren't happy with Laurel's new crime-fighting persona, but they may just have to deal with it as Brick makes his move on the Glades.
A former whiz-kid from S.T.A.R. Labs returned to take revenge on Harrison with a killer sound. Meanwhile, Iris joined the city newspaper.
Team Arrow is struggling to keep Starling City safe in Oliver's absence.
As Barry and Joe came to grips with Iris moving in with Eddie, Captain Cold returned with a new plan for dealing with the Flash.
Alicia and Prady squared off in two kinds of debates while Chicago braced for a potential riot.
One last good turn of events may prevent Cary from going to prison, but will it happen in time? Meanwhile, Alicia's debate prep got off to a messy start.
This was it: Team Avatar vs. Kuvira and her giant mecha.
Harris did his best to prevent the crew from discovering the truth, but an outside investigator and Christa's new abilities made doing so quite challenging.
Five decades into a lengthy mission, the inhabitants of the Ascension began coming undone in the wake of a young woman's murder.
Kuvira's plans to attack Republic City were set in motion sooner than expected... and no one was expecting her latest weapon.