“I’m going to teach you everything I know, starting with phasing,” says Barry Allen (Grant Gustin) to Wally (Keiynan Lonsdale) while they’re training to keep Iris (Candice Patton) safe from Savitar in The CW’s comic-book inspired fantasy action series, The Flash.

As season three episode 12 begins, The Flash and Kid Flash are getting ready to have a speedster race and Barry is trying to get a very excited Wally to focus and not look at it as a competition but as an opportunity to improve his speed. Back at S.T.A.R. Labs, Cisco (Carlos Valdes), H.R. (Tom Cavanagh), Iris (Candice Patton), and Caitlin (Danielle Panabaker) are making bets on who will win the race. Cisco, Iris, and Caitlin bet on Barry and H.R., who’s been working with Kid Flash, bets on Wally. The speedsters race and it’s close but Barry uses his phasing ability to go through a building while Wally has to go over it. Wally is disappointed but Barry tells him he needs to learn how to phase and use all his powers when he’s “out in the field.”

Barry arrives at a crime scene where Julian (Tom Felton) is already examining a dead body that’s decomposed quite a bit. Joe (Jesse L. Martin) arrives and is surprised how far along the body’s gone considering the victim died only last night. Barry suggests taking the body to S.T.A.R. Labs to use the equipment for a 3D autopsy since the CCPD doesn’t have one and Julian reluctantly agrees. Barry and Joe head inside and find Iris covering the story for her website. Joe asks his daughter and Barry to join him at Jitters the next day for coffee so they can meet Cecile’s daughter, Joanie. They agree and are happy to see Joe excited about his new relationship with Cecile. Iris tells Barry she needs to show him something at S.T.A.R. Labs.

Once there, Iris reveals she’s really scared they aren’t changing the future, pointing out the restaurant where the murder happened is the one that reopens under a new name on the night she dies in the future. Barry reassures her he will get Wally fast enough to stop Savitar from killing her and asks if they should tell Joe. Iris says no, concerned he’ll just worry about something he can’t do anything about.

Barry takes Wally to the workout room to teach him phasing, and their training session doesn’t go well. It seems even though Wally is trying and going fast, he doesn’t understand how to phase. It doesn’t help that Barry is having a hard time teaching him by just encouraging him with “try it again” and “you can do this” prompts. Finally, Barry explains to Wally that he needs to feel all the energy around him and in him and make himself phase at a different frequency. Wally still keeps crashing into the reinforced wall Cisco made instead of passing through it. Barry’s called away to another crime scene and tells H.R. and Cisco to make sure Wally keeps training.

In the medical lab, Julian and Caitlin are working together to perform the autopsy, with Julian getting on Caitlin’s nerves with his smug and rude behavior. The autopsy ends before it can even begin when Caitlin unzips the body bag to discover the body is barely together and almost dust. Julian says it’s not a virus and Caitlin points out it must be from some form of metahuman.

That night, jazz musician Julio Mendez is loading up his car when a stranger approaches and says he’s a fan and asks to shake his hand. The musician agrees and feels pain as his hand begins to turn dark and rot. The effect moves all across his body.

The next day, Barry, Joe, and Julian are at the crime scene and Barry recognizes the name of the victim as a police captain in Flashpoint. He asks if Julian has a photo of the first victim and he does. When Barry sees it, he remembers that he was an officer in Flashpoint. Realizing the meta killer is focusing on cops, Barry is worried for Joe and suggests he lay low until they find whoever is doing this, suggesting he cancel the date at Jitters. Joe blows it off saying he’s faced worse and if trouble does show up he’ll have his two speedster sons to protect and help him. Barry speeds the new victim’s body to S.T.A.R. Labs so Julian and Caitlin can, hopefully, find some DNA of the killer and also a clue as to how he’s doing this to his victims.

Back at the medical bay, Julian is once again being rude to Caitlin. (He lets her know he’s used to working alone, especially during autopsies.) Caitlin is working slowly and meticulously, which is annoying Julian until she discovers the skin on the right hand of the corpse is darker than the rest. She believes this has to be the point of contact with the killer. Julian jumps in and takes a sample of the skin from the hand to do a DNA workup, with Caitlin saying she thought Barry was exaggerating when he complained about Julian but now she sees his point. When they look at the DNA, they see two different strands and Julian admits to Caitlin he’s seen part of the murderer’s strand before on the Alchemy mask. This means Julian created this metahuman named Clive Yorkin (Matthew Kevin Anderson) when he was Alchemy, and Yorkin can rapidly disintegrate anything he touches. Caitlin and Julian call Barry to tell him what they’ve discovered.

Unfortunately, Barry gets it while on the Jitters date with Joe, just as Clive walks in looking to kill Joe. Barry and Joe tell the other patrons to leave and Yorkin allows them, saying he only wants Joe. Wally slips out after seeing Barry nod because Barry can’t make his way to the exit since he’s on the second level next to Joe and it would reveal to Cecile and her daughter he’s The Flash. Joe fires his gun but the bullets disintegrate the second they touch Yorkin’s body. Yorkin is about to touch the beams holding up the second level when Wally re-enters as Kid Flash. Kid Flash can’t touch Yorkin and looks up to Barry for ideas while being mocked by Yorkin. Barry motions to Wally to use his tornado arms which works, blowing Yorkin off his feet and through the rear glass doors.

Back at S.T.A.R. Labs, Joe is refusing to hide out and instead wants to check on Cecile. Iris gets upset with him for being so reckless about his well-being. He tells her no one on their team is going to die today and she finally breaks down and tells him what Barry saw in the future – that Savitar kills her. Extremely upset about what she has just told him and that they kept it a secret, Joe lashes out at Barry saying he knows better and knows how much Iris means to him. Joe goes off with Iris following him.

Barry heads over to CCPD to try to find something on Clive Yorkin that might help them. Julian feels terrible he gave Clive his powers when he was Alchemy, and even though Caitlin tries to comfort him and tells him it’s not his fault, he tells her that people are responsible for their actions and only say that to make themselves feel better. Caitlin, looking hurt, asks if he thinks that’s what she’s doing and after he hesitates to answer, she says, “I’m regretting bringing you into S.T.A.R. Labs,” and walks away deeply upset.

At Iris and Barry’s home, Iris is trying to get in touch with her father when Clive disintegrates their door and enters. He’s decided that if he really wants to hurt Joe, he’ll kill her instead. Iris sets off the alarm signal to S.T.A.R. Labs and Wally tells Cisco he’s closer than Barry and he’ll handle it. However, as fast as Wally is, he’s not fast enough to get there before Clive touches Iris’ arm. Wally races her to S.T.A.R. Labs.

Team Flash doesn’t know what to do to stop the spread of the decay in Iris’ arm. Barry arrives last and asks what happened and is brought up to speed. He yells at Cisco for not calling him to save Iris and sending Wally who feels guilty about not keeping his sister safe. Cisco realizes the way to slow the necrosis is to freeze Iris’ arm. They all look to Caitlin who says she can’t, with Barry backing her up, arguing that if she freezes Iris too much she’ll have permanent nerve damage. Iris, scared and desperate, tells Caitlin she trusts her. Caitlin says she doesn’t want to and is scared she’ll lose control and become Killer Frost. Iris says that Caitlin is stronger than she knows and she can do it. Seeing no other option, Caitlin takes off her power-reducing cuffs and solar-powered necklace and uses her powers to freeze Iris’ arm. Barry, kneeling by Iris, watches closely over both of them. He asks Caitlin if she’s okay while she freezes Iris’ arm and she says she’s in control. The necrosis stops…for now.

Barry goes to find Wally knowing that he was out of line by saying what he said. Wally feels terrible but Barry tells him none of this is his fault. Barry admits he hasn’t been a good enough teacher and has been letting him coast on his natural talent. Barry promises Wally the next time he’s out there on his own facing the enemy he’ll be able to take him down because Barry is going to inspire and teach Wally how to use his abilities. (This is a great scene between the two, really showing a maturity in Barry that wasn’t there in the first two seasons.) Cisco interrupts, telling them he and H.R. have found a way to catch Clive.

Cisco says he’ll vibe to Flashpoint and see who Clive’s next victim will be. It works, and Cisco sees that Clive’s arresting officer was Laura Stone who in this reality is a private investigator. Joe heads out to warn and watch over her while the rest of the team figures out a way to stop someone you can’t touch. Joe finds her at the train station on a case following a cheating spouse.

Meanwhile, Julian has been looking for a way to stop Clive and tells Barry he believes that a small dose of a speedster’s blood will neutralize Clive’s powers. The alarm at the medical bay goes off and Barry and Julian run in to find Caitlin freezing more of Iris’ arm to stop the decay which has started to move up her arm. Barry sees Caitlin’s eyes go from brown to crystal blue and says her name. “I’m in control,” says a weary Caitlin and suddenly she stops freezing Iris’ arm. Caitlin’s voice is cold as she suggests letting Iris die and now Barry is desperate. Julian steps in first and tells Caitlin that she’s Caitlin Snow and she’s helping Iris. Caitlin’s eyes waver from brown to crystal blue and Julian tells her not to give in, that he knows the inner fight she’s going through. He went through it too but was weak and gave in to it and hurt so many people, but she won’t because she’s the strongest person he has ever met. As he says this, he works his way over to Caitlin and touches her arm. “Now, Caitlin, help Iris,” says Julian, and Caitlin takes control once again and uses her powers to stop the decay from continuing.

The team goes from one emergency to another when an alarm goes off and Team Flash see that the train Joe and Laura Stone are on is about to crash into debris that Clive made using his powers. The Flash and Kid Flash race there but only have moments before the train is going to crash. It’s moving too fast for them to get everyone out in time. Barry tells Wally he’ll vibrate while on board the train to phase it through the debris. (This is a great action scene – one of the best this season.) It works but leaves The Flash weak, so it’s up to Wally to take down Clive. With Barry’s encouragement and walking him through it, Wally phases through Clive with an open cut on his hand, injecting Clive with his blood and neutralizing his power.

At S.T.A.R. Labs, Caitlin and Julian come up with an antidote for Iris using Clive’s DNA. Joe makes everyone promise no more secrets and if they’re going to save Iris, they have to work together and be honest with each other. Everyone agrees. Julian walks out of the meeting saying he’s heading over to the CCPD to try to find the last metahuman he created. Caitlin catches up to him and thanks him for helping her not become Killer Frost. He gets on the elevator to leave and Caitlin asks if he’d like to go get a drink. Seeming very pleased and smiling for the first time in the episode, Julian says yes and he and Caitlin leave together. (Please, don’t let Julian be Savitar or his willing henchman. Caitlin has had enough heartbreak for three lifetimes!)

At their apartment, Barry has had a new front door installed with multiple deadbolt locks because he wants Iris to feel safe. Iris tells Barry she loves him and now knows he’ll always do whatever he can to keep her safe.

The final scene is at S.T.A.R. Labs with Wally practicing phasing when Jesse Quick (Violett Beane) comes through a breach. Wally’s happy to see her but quickly realizes something is wrong. He asks her what’s up and Jesse tells him Grodd has kidnapped her father and taken him to Gorilla City.

The Flash Season 3 Episode 12 Review:

Suspenseful and action-packed, season three episode 12 shows just how effective Team Flash is when they work together and support each other. It also finally brings Joe into the loop of what Team Flash is fighting to stop: Iris’ death at the hands of Savitar.

The two stand-out performances in this episode were delivered by Jesse L. Martin and Grant Gustin. Jesse L. Martin delivers a moving and emotional performance as his character is told about the dark future for his beloved daughter. The scene where Iris reveals to Joe what Barry saw in the future and that they’ve known for over a month is almost uncomfortable to watch. The look of devastation on Martin’s face is powerful, as well as is his anger toward Barry for keeping it from him.

Grant Gustin really shines in this episode, showing a more mature Barry as he takes on the role of teacher and mentor to Wally. The scene in which he explains to Wally that it’s his fault Wally isn’t learning faster because he’s been letting him coast and not truly inspiring him to learn shows an adult Barry Allen. Also impressive is the great train rescue where The Flash vibrates and phases the train full of people through the debris. It’s hands-down one of the best action scenes in the show since the series began.

With the arrival of Jesse to Earth-1 and her father being a prisoner of Grodd’s on Earth-2, here’s hoping Team Flash can travel there, save Harry, and stop the Gorilla attack on Earth-1 that they saw in the news headlines in the future in the hopes of altering Iris’ fate.

GRADE: B+