When a powerful alien threat arrives on Earth under mysterious circumstances, Barry, Iris and the rest of the team are pushed to their limits in a desperate battle to save the world.

Despero warns The Flash that great tragedies will lead to Armageddon. Barry doubles down on proving his innocence, but a devastating revelation pushes him to seek counsel from Black Lightning.

Barry meets Black Lightning at the Hall of Justice after things take a dire turn with Despero. Iris suspects something is off with Despero's vision of the future so she seeks help from a powerful ally.

Barry is shocked when Eobard Thawne returns in the most unexpected way, and with a tie to a loved one. Damien Darhk offers advice to Barry but there is a catch. An epic battle begins with The Reverse-Flash against The Flash and Team Flash.

Barry must decide whether to let his greatest enemy die, or save his life.

Nora and Bart travel back to the future, only to discover that their actions in 2021 have altered 2049.

When a criminal invades the CCPD, Barry and Kramer must trust and rely on each other if they are going to make it out safely. Caitlin learns a valuable lesson while out with Snow and Mark.

Barry trusts his instincts during a murder investigation, believing the suspect, despite the overwhelming evidence against him. Iris gives Allegra an opportunity to be a mentor.

Barry and Team Flash get closer to figuring out the Fire Meta but no closer to finding him. Iris, needing a distraction, follows a story to Coast City.

Barry's desire to keep the team safe is tested when Frost recklessly courts danger while trying to stop the Black Flame. Iris tries to help a teen girl reunite with her mother but unintentionally does more harm than good.

Barry and Chester may have found a way to stop the Black Flame from hurting anyone else; Caitlin decides to handle a situation on her own, possibly putting more innocent lives in danger.

With a new Meta terrorizing the city, Joe lends a hand to the local authorities. Barry gets an assist from Cecile who helps to track the mass murderer.

Team Flash is under attack, and each must fight to save not only themselves but each other.

Team Flash uses the distraction of a bank robbing Meta to detract from the grief of losing someone they love.

The Flash gets an assist from XS; CCPD enlists Chester for help when a mysterious device is found at a crime scene.

The Flash gets blasted with a shockwave forcing his body to age prematurely.

The Flash goes off the grid to look for answers about a new Meta in town. Allegra tries to protect a friend at CC Citizen Media.

A new speedster in town gives The Flash more than he bargained for. Cecile's powers experience a growth spurt, allowing her to aid Team Flash on an entirely different level.

A fight looms for The Flash and team. Iris discovers the cause of her time sickness.

With The Flash still reeling from everything that just happened, the rest of the team rallies to support him when he needs it the most.