The Flash recap: Nash battles Thawne and confronts his past

The Flash hit us with yet another dark (but compelling) installment. Written by Lauren Barnett and Sterling Gates, "The Exorcism of Nash Wells" digs into Nash Wells's tragic past and reveals what exactly is going on with all of the Wells he's been seeing.

The episode wastes no time revealing what happened to Kamilla. Speaking to Mirror-Iris and the newly created Mirror-Kamilla, whose creation wasn't planned, Eva reveals that Kamilla is simply no longer a problem. She doesn't say dead, which means she's still alive out there. Anyway, Eva tasks her two minions with recovering a device she built called the prismatic refractor, which will apparently help free her from her prison.

Of course, Team Flash has no idea that anything is up with Iris and Kamilla because they haven't noticed anything weird yet and more importantly, they have their hands full with Thawne, who is fighting to take control of Nash's body, and Barry losing his speed. By examining Nash's brainwaves, Caitlin discovers that his brain is currently holding every Wells in the multiverse, which explains why he's been seeing them. During the examination, Thawne escapes from the pipeline and tries absconding with the time sphere, but Barry, Caitlin, and Cisco stop him before he does. And Caitlin and Cisco stop Barry from Thawning Thawne (read: phasing his hand through his heart). Because his emotions draw on what remains of his powers, Caitlin orders Barry to leave so that he doesn't use up any more of his remaining Speed Force.

Cisco and Caitlin hook Nash up to a device that's supposed to draw Thawne's negative tachyons out of his body, and Cecile taps in to monitor Nash's psyche during the process. Unfortunately, this proves to be quite difficult because Thawne's hold on Nash is stronger than they realized. In fact, Thawne digs through Nash's memories and forces him to confront a particularly tragic one that he's been avoiding.

In the episode's first flashback to eight years ago on Earth-718, we see Nash meet Maya, Allegra's doppelganger, for the first time. When Nash realizes that she's not only smart but an orphan, he decides to take her under his wing and teach her how to myth-bust. Her first lesson? "The prize is everything." This rule, though, ends up being the thing that eventually leads to her death. Dredging up this memory weakens Nash's control over his body because he becomes trapped in a cycle of remorse and regret, which is visualized by Nash cowering in the corner of a tunnel that leads to another memory he's trying to avoid. Sure, it's not the most exciting thing visually, but Tom Cavanagh sells it with his moving and plaintive performance as Nash. (As always, Cavanagh is amazing as Thawne.)

While Cisco and Cecile work on Nash, a metahuman/Carver minion named Sunshine, who can control sunlight, breaks into Mercury Labs to steal the prismatic refractor right as Iris and Kamilla show up to do the same. Not wanting to blow their covers, the duo call the Flash; however, Caitlin tells Barry to stay behind at S.T.A.R. Labs and conserve his speed while Frost handles Sunshine. But Barry being Barry, he ignores her, takes Velocity X, and joins her out in the field — only for his body to reject the steroid, causing him to collapse mid-battle. In the chaos, Sunshine burns Frost, reopening her wound from her fight with Doctor Light. Luckily, Joe and the CCPD arrive in time to stop Sunshine from stealing the refractor.

Back at S.T.A.R. Labs, Barry feels even worse for failing in the field. Mirror-Iris, on the other hand, is more concerned with the refractor, which Joe plans on handing over to A.R.G.U.S. because he thinks Carver has a mole in the CCPD. Joe actually has to remind Iris to, you know, check in on Barry, who obviously can't imagine being a superhero without powers, or at least limits on his powers. Mirror-Iris does her best Iris impression and reminds him that metas have limits, but people don't and he can still be a hero as Barry Allen. That pep talk gives Barry an idea for how to handle Sunshine.

Over at the CCPD precinct, Sunshine attacks Joe and Singh as they hand the refractor over to A.R.G.U.S. Barry shows up in time, grabs the refractor, and lures Sunshine on a chase up to his lab that ends with him trapping her in the darkroom, which negates her powers and allows A.R.G.U.S. to arrest her. It's a pretty clever plan and the whole sequence, like last week's opening, feels unlike any other action set-piece the show has attempted before. I also loved how the writers wrapped the Sunshine plot up with almost 20 minutes left in the episode and didn't drag it out more than necessary.

Having saved the day, Barry returns to S.T.A.R. Labs determined to help Nash, too. With Cecile's powers, Barry and Cisco enter Nash's mind to give him back-up against Thawne. There, Thawne taunts Barry with Nora's death, which is a great moment because it's clear that the writers haven't forgotten that Barry is probably still grieving that loss. At the same time, Cisco uses his recent experience with grief to convince a cowering Nash to get up and confront his remorse. So, Nash enters the memory he was avoiding, revisits Maya's death, and accepts his role in it.

Had he not taught her that "the prize is everything," she would've let go of the treasure they were seeking and could've used both hands to lift herself up when she was dangling from a cliff. That's enough to overpower Thawne, whose tachyons are dispersed into the atmosphere as Nash regains control of his body.

But don't worry: Thawne isn't dead. The script makes that very clear! He's just formless and needs to possess a new body, which means we'll see him again down the line. (Also, all of the Wellses are still stuck in Nash's mind, which means we'll still get the occasional Harry visit from time to time.)

This was a very busy episode for Barry because fighting Thawne once again helped him figure out the key to creating a new Speed Force: They need to consult Nora's journal because Thawne taught her how to do it. Caitlin expresses some concern over attempting this since Thawne's Speed Force was fueled by hate and hurt everyone who came into contact with it, but Barry is sure there's won't be like that because it'll be powered by love for Nora. In other words, there's another reason Barry was the Paragon of Love. Meanwhile, it's revealed that Mirror-Iris and Mirror-Kamilla stole the refractor during the commotion at the precinct and they hand it over to Eva as the episode ends.

Grade: B

Wall of Weird:

• Cisco convinces Nash to hang around and try to fix things with Allegra. I really liked that beat because Cisco references how he and every previous Wells didn't start out as friends and getting to that point took some work, but it was worth it.
• I really hope Singh isn't Carver's mole in the CCPD. He seemed too eager to blame Sunshine for the suspicious case files.
• The Flash returns April 7!

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