‘The Flash’ Season 3 Episode 20 Recap and Review: I Know Who You Are

The Flash Season 3 Episode 20 Killer Frost
Danielle Panabaker as Killer Frost in ‘The Flash’ season 3 episode 20 (Photo: Katie Yu © 2017 The CW Network)

“I know who you are,” says Barry (Grant Gustin) when he’s face-to-face with Savitar as season three episode 20 of The CW’s The Flash begins. We then jump back to 16 hours earlier to show Joe (Jesse L. Martin) and his girlfriend Cecile (Danielle Nicolet) arriving home after a training run for the upcoming marathon which Joe is thinking about sitting out. After a little fun banter, Cecile lets slip that she loves him. That surprises Joe and he doesn’t say it back. Luckily for him, he’s summoned to S.T.A.R. Labs and excuses himself from the awkward conversation.

Barry brings Team Flash up to speed about what Barry from 2024 told him and they’re all in agreement they should find this physicist named Tracy Brand (Anne Dudek). Upset, Julian (Tom Felton) asks why they aren’t searching for Caitlin. Cisco (Carlos Valdes) reminds him that Joe and Barry have been searching the city for her, he’s been vibing trying to get a lock on her, and they’re using the satellites and sensors to try to find her. The two begin arguing and it quickly gets heated, so Barry is forced to break it up. They get a hit on where to find Tracy and Barry, Cisco, and H.R. (Tom Cavanagh) head to Central City University to talk to her.


Once they find her, Barry has to literally put out a fire she created in her lab destroying some of her work because she has been denied any future funding. The gang’s surprised to find this younger and not-yet-published scientist is quirky and unsure of herself. H.R. and Barry try to talk her into continuing her work when Killer Frost (Danielle Panabaker) shows up in a new black outfit (it’s a big improvement over her Earth-2 doppelganger costume) to kill Tracy. Barry moves Tracy out of Frost’s line of fire just in time and tells H.R. to get her out. Frost hits Barry with a cold blast but just to knock him out. Cisco slowly steps forward saying how she’s full-on Killer Frost now, with a new outfit and everything. Frost replies, “No more pencil skirts for me.” Cisco tells her he doesn’t want to hurt her but she replies, “You won’t.” (Sounds familiar.) Cisco freezes and Caitlin blasts him with a cold blast but, again, not a deadly one. Barry is able to get up and uses a make-do flame thrower to cause Frost to flee.

At the CCPD, a sketch artist finishes drawing Killer Frost. Joe takes the drawing and conveniently misplaces it while Cisco and Julian erase the university’s video footage of the attack, protecting Frost from being identified by the authorities.

Killer Frost reports to Savitar, telling him Tracy got away. She explains Barry and Cisco were already there and Savitar’s displeased. He’s disappointed that despite the fact she calls herself Killer Frost, she hasn’t killed anyone yet. He asks if there is more Caitlin Snow in her than she told him and she responds by asking if he thinks she let them get away on purpose. “Did you?” he asks and she looks away, not answering him. Savitar approaches Frost, who seems a little afraid, and tells her they can both be gods free of human feeling and despair…but she has to kill the girl.

H.R. catches up to Tracy at Jitters, trying to keep tabs on her. He buys her a specialty drink called “Zoom” and chats about how impressed he is with her scientific theories, which he’s able to recite thanks to Cisco feeding him info via his earpiece. Julian, who’s with Cisco, brings up how he saw the video footage they erased and how it looked like Cisco didn’t try to fight Killer Frost. Cisco becomes agitated and tells Julian to focus on the job at hand.

H.R. notices that his coffee is frozen and tells Tracy they need to leave now. He takes her outside, yelling they need help when a deadly icicle almost hits Tracy in the head. Fortunately, The Flash pulls her out of the way in the nick of time. Killer Frost walks up and Barry tells H.R. to get Tracy to safety while Julian tells Caitlin to stop. She just smiles, eerily. “So what, you’re Savitar’s stooge now?” asks Barry. “Better to reign in Hell and all that,” replies Frost. She then creates a frozen ice wave and surfs around Central City trying to grab H.R. and Tracy. The Flash chases her and maneuvers her back to Jitters where a waiting Cisco is supposed to knock her out with his powerful vibe so they can take her back to S.T.A.R. Labs. But Cisco once again freezes, seeing Caitlin’s lovely, friendly, smiling face from memory as Frost approaches. She uses the opportunity to send a cold blast at Cisco which The Flash intercepts, pushing Cisco out of the way. Barry gets hit instead and falls down a flight of stairs.

Frost finishes up her ice surfing and strides down the stairs with a large icicle in her hand. “Savitar told me I can’t kill you but I can’t have you following me all around. It was the left leg last time, right?” she asks a winded The Flash. Frost stabs him in the same leg with the icicle saying that scar tissue is more sensitive than regular tissue. “This isn’t you,” yells Barry in pain. “It is now,” replies Frost as she leaves the wounded speedster.

Back at S.T.A.R. Labs, Team Flash bring Tracy up to speed about her future and everything she’ll accomplish. They warn her that if she doesn’t invent the device to trap Savitar now, someone they love will die. Feeling overwhelmed, Tracy walks out and H.R. says he’ll go talk to her. A little later Julian visits Cisco in his workshop and asks why he didn’t stop Caitlin when he had the chance. Cisco tries to walk away but Julian won’t let him and finally Cisco admits he’s afraid of killing Caitlin with his powers. He’s not sure he can control it and if she’s attacking someone like Joe or Barry or Julian, he might have to kill her to stop her. “She’s my best friend. I’d rather die myself,” says Cisco as he walks away.

In another part of S.T.A.R. Labs, Barry encourages Joe to tell Cecile the truth about Team Flash if he loves her. That’s exactly what Joe would tell Barry to do if the situation was reversed. Their heart-to-heart is interrupted by H.R. who informs them Tracy is gone. They open her future hologram to search for her and H.R. realizes where she is. He finds her at Central City Park in front of a statue of Galileo. He gives her a much-needed pep talk about believing in herself and that he knows she’s a genius and she just needs to find her confidence.

Back at Joe’s house, Cecile shows up and wants to know what’s really bothering him. She’s concerned it’s what she said earlier that day and he tells her that his life is very complicated and he thinks it’s best if they stop seeing each other. Upset, she tells him she’ll see him around the office and leaves. There’s a knock on the door and Joe opens it to find Killer Frost holding Cecile with a sharp icicle to her throat. Frost says she’ll text him in an hour with instructions on where to bring Tracy. If he doesn’t, Cecile dies. Killer Frost then hits Joe with a cold blast when he goes for his gun.

Barry tells Team Flash he has a plan to get Cecile back – and maybe even Caitlin. Just before they leave, Julian reminds Cisco his powers come from a good place, from love, and that he’ll stay in control when he battles Caitlin and he won’t kill her.

The Flash Season 3 Episode 20
Grant Gustin as The Flash, Jesse L. Martin as Detective Joe West and Danielle Panabaker as Killer Frost (Photo: Dean Buscher © 2017 The CW Network)

Barry, Joe, and Tracy follow Frost’s instructions and show up at an old factory where Cecile is being held. She’s tied up to a chair but unharmed. Frost appears telling Cecile that killing her is nothing but killing Tracy is everything. Barry tries to talk to Caitlin, attempting to convince her they’re family, but Frost finishes every word of his speech as though she knows exactly what he’s going to say. Barry asks how she’s doing that and she tells him Savitar told her everything he would say. “You two are more alike than you know,” says Frost with a bright smile. “It’s all history to him,” she continues. Frost then reveals she knows Cisco is hiding up in the rafters where she’s placed an explosive. She uses a remote device and Cisco comes crashing down to the ground, unconscious but alive.

Frost tries to kill Tracy but Barry takes the blast of cold. She renders him briefly out of commission by freezing him, pinning him to the floor. Joe pulls his gun but hesitates to shoot because it’s still Caitlin in there somewhere, so Frost freezes his gun. Finally snapping into action, Cisco hits Frost with a vibe power blast. She gets up to take him on and Joe uses this distraction to rescue Cecile. Frost shoots a continuous blast of cold at Cisco while he fires back with his vibe powers. At first Frost is winning, pushing back Cisco but then Cisco focuses and uses his powers without holding back and it’s more than Frost can handle. The vibe hits her and throws her back into a wall, knocking her out. Barry is finally able to vibrate out of the ice while Cisco takes a blood sample from Frost, apologizing to Caitlin for hurting her but saying he had to to save her. Just as they’re about to take her to S.T.A.R. Labs, Savitar shows up telling Barry, “My ascension is nearly at hand.” He grabs Killer Frost and speeds off.

At S.T.A.R. Labs, Cisco wants to know how Caitlin knew he was in the rafters and how she was finishing Barry’s sentences. “Can she read minds now?” he asks, but Barry tells him she said Savitar told her. Julian tells the gang the blood sample Cisco took of Caitlin in full Killer Frost mode could lead to him finding a cure. Iris (Candice Patton) asks why Savitar saved Killer Frost instead of going after Tracy, and Barry says he must need her for something and they need to figure out what that is. Tracy tells H.R. she believes Savitar’s suit neutralizes the charge around him and she thinks they can build a device to harness its power and use it against him, trapping him in the speed force.

At the CCPD, Joe checks on Cecile to see how she’s doing and finally tells her he loves her. He made a mistake thinking by breaking up with her he was protecting her. Joe then sits down and reveals everything about Team Flash.

Back at the West home, Wally (Keiynan Lonsdale) is telling Barry and Iris about visiting Jesse on Earth-3 when Joe comes in and says he told Cecile about them. As Joe credits Barry with giving him the advice to tell her if he loves her and if they don’t have love who would they become? Barry starts to go over everything that’s happened and been said including Killer Frost saying that Barry and Savitar are more alike than he knows. Barry excuses himself from the Wests and races out. Next we see The Flash in the middle of the dark street where he was when the episode began.

“I’m here,” yells the Scarlett Speedster twice and Savitar shows up, facing him. “I know who you are,” says Barry. “It’s about time,” replies Savitar. “Yes, it is. Everything with you is about time. The past, the present, the future…you know all of it right and you know everything about me, about Joe, Wally, and Iris. You know our strengths. You know our fears. You know how much we love each other and you know how to use that love against us. All this time we thought we couldn’t stop you because you were one step ahead but that’s not it. You were there. You lived it. You remembered it…when you were me,” says Barry, finally realizing he’s been fighting a future evil version of himself this whole time. Savitar bends down and his armor opens to reveal a future Barry Allen with a badly scarred face and discolored eye. “Like I told you in the beginning, I am the future Flash,” says the Evil Barry Allen.

The Flash Season 3 Episode 20 Review:

Action-packed and surprising, episode 20 titled “I Know Who You Are” finally reveals the identity of the “God of Speed” Savitar and pits Killer Frost against Team Flash. It’s an extremely fast-paced and exciting episode with the best super power battles in the series to date.

The two stand-out performances go to Carlos Valdes as Cisco and Danielle Panabaker as she brings to life Killer Frost. Valdes perfectly captures the heartbreak and pain he feels having to go up against his best friend and possibly hurt or even accidentally kill her in battle while trying to protect Barry and the others from her wrath. The scene where Cisco is about to blast Killer Frost off her ice wave and he flashes on Caitlin’s lovely face smiling at him is truly heart-wrenching.

Panabaker brings this much darker and more vicious version of Killer Frost to life as she tries to kill Tracy on the orders of her new partner, the evil Savitar. The eerie smiles and her crystal blue eyes that gleam every time she taunts or wins a round with Team Flash are extremely effective in helping to show her character’s malice. Panabaker also subtly shows how Catlin is still alive in Frost under all the cold in the scene where Savitar tells her she has to kill the girl and Frost looks uneasy and unsure of herself.

The action scenes, battles, and special effects are excellent throughout the episode, especially the chase through Central City when Killer Frost is surfing on her ice wave. This particular scene features some groundbreaking visual effects we haven’t seen on television before.

With Savitar’s identity revealed to Barry, the real question is how can he and Team Flash stop an evil, all-knowing version of himself from killing Iris? And, how can Team Flash save Caitlin from her evil alter ego, Killer Frost.

GRADE: B+