The Flash

In the season four premiere, Cisco (CARLOS VALDES) makes a risky decision to break Barry (GRANT GUSTIN) out of the Speed Force.

Barry has his hands full when he takes on a dangerous meta, while also confronting obstacles in his personal life: like abandoning Iris to balance the Speed Force.

When Barry and the team are hit with a string of bad luck, they realize it's the handiwork of a new meta, Hazard (SUGAR-LYN BEARD), who's got the ability to manipulate luck.

Cisco is shocked when Gypsy (JESSICA CAMACHO) and her father, Breacher (DANNY TREJO) show up on Earth-1. And Breacher really dislikes him!

Felicity (EMILY BETT RICKARDS) comes to Central City to help the girls celebrate Iris's bachelorette party, while Caitlin gets a threat from her old boss, Amunet (KATEE SACKHOFF).

Determined to crack the identity of The Thinker, Harry enlists Cisco's help to summon the ultimate think tank – a roundtable of the brightest Harrison Wellses from various Earths.

Barry comes face to face with DeVoe (NEIL SANDILANDS), whose past is revealed through flashbacks. Meanwhile, Iris puts the final touches on the wedding, which is a week away.

When villains from Earth-X attack the wedding ceremony of Barry and Iris, the Green Arrow, Supergirl, The Flash and White Canary unite their teams to save the world.

While Amunet kidnaps Caitlin, The Thinker traps The Flash in a speedster-proof prison. With the clock ticking, Iris is forced to choose which one of them to save.

As Barry's trial for the murder of Clifford DeVoe begins, Iris and Joe must decide how far they are willing to go to keep Barry out of prison.

While Barry struggles with his trial, Ralph must rise up to protect Central City when a familiar villain returns.

When a meta who can shrink anything he touches battles Team Flash, Cisco and Ralph get caught in his crossfire and are shrunk to miniature versions of themselves.

After hearing that Amunet has struck a deal to buy all of the metahumans in Iron Heights, Barry must decide if he should expose his powers in order to save his cellmates.

After learning that DeVoe is targeting everyone who was on the bus, Ralph decides he doesn't want to be a hero anymore – he just wants to stay alive.

When a nuclear bomb detonates in downtown Central City, Barry, Jesse Quick and Jay Garrick slow down time by entering Flashtime to save the city and everyone in it.

When Team Flash confront a new meta, Melting Pot (LEONARDO NAM), he accidentally takes Barry's speed away and gives it to Iris, making her the speedster.

While Barry and Ralph clash over their different approaches to finding the remaining bus metas, Breacher (DANNY TREJO) returns to ask Cisco a favor.

When Barry & Team Flash find a way to enter The Thinker's lair, Ralph considers crossing a dangerous line to defeat DeVoe. Meanwhile, Joe is concerned by Harry's recent behavior.

When Barry needs help transporting a dangerous meta, he calls on Leo Snart aka Citizen Cold (WENTWORTH MILLER). Meanwhile, Cisco becomes suspicious of Harry.

Barry and Team Flash team up with Gypsy (JESSICA CAMACHO) to try to thwart the Thinker's plan. Meanwhile, Cisco and Gypsy have a heart-to-heart talk about their relationship.

With DeVoe's Enlightenment device nearly complete, the Team turns to Amunet Black for help. And Harry hits an all-time low when the Council of Wells kicks him out.

When DeVoe assaults an A.R.G.U.S. facility for his Enlightenment Machine, Barry realizes the only way he can stop him is if he allows Cisco and Caitlin to accompany him.

In the Season Four finale, Team Flash gets help from a surprising ally in their battle against DeVoe.