"Power Outage" begins 10 months in the past, on the night of the Particle Accelerator's explosion. Farooq is watching the Particle Accelerator experiment from a vantage point on top of an electricity transmission tower, with his friends on the ground below. When the accelerator explodes, the shockwaves hit Farooq and his friends. The explosion and and tower electrocute Farooq before the towers collapses on top of Farooq’s friends, killing.
In the present, Wells enters his secret chamber he used in the series premiere. Speaking into a recorder, Wells dictates Barry’s progression as The Flash. He says that Barry isn’t meeting his full potential, but then he pulls the 2025 news article of the Flash’s demise in the Crisis, and says that the future still remains “in tact.” He then calls Barry into STAR Labs, where he says that the Flash needs to kick his speed “up a notch” and help STAR Labs use his powers to cure illnesses. The lecture is cut short though, when Barry is called to a homicide scene.
At the scene, the victim is left a charred husk from extreme electrocution. Though the victim’s faced was too fried to identify, Cisco and Snow use STAR technology to identify the victim. Their progress is cut short however, when Cisco gets an energy reading from a power plant that matches what was on the corpse. Barry races to the power plant, where he sees Farooq feeding off of the plan’t’s energy. Farooq senses the immense energy resting in Barry and sucks it from him like a mosquito. When Farooq is finished, Barry can’t tap into his suppressed. He’s powerless.
Barry has to take a cab back to STAR Labs, where Snow says that Farooq couldn’t have changed Barry’s super accelerated genes. Wells promises that he will find a way to restore Barry’s speed. Barry leaves for Central City Police Department, where he meets Joe and Iris. Barry tries telling Iris that maybe the Flash won’t be able to help Central City anymore. On his way out, Barry see the police bring William Tockman, a.k.a Clock King, into the precinct.
Concerned for the Flash’s future, Wells goes back to this time chamber. He tries searching for The Flash or Barry Allen in the future’s news archives, but no matches appear. For now, The Flash doesn’t exist in the future. Elsewhere in the lab, Cisco identifies Farooq as the man who stole Flash’s power. Almost on cue, STAR Labs security cameras pick up Farooq standing outside its doors, demanding to speak with Dr. Wells. He reveals that he is the man from the episode’s opening, and blames Wells for his friends’ deaths.
When the gang doesn’t let Farooq in, he rips opens their power box and saps all of their electricity. He plunges the entire city in a power failure—including the police department. Clock King uses the temporary pandemonium as chance to subdue his guards and draw a gun on Joe and Iris. He holds the entire precinct hostage.
Desperate to save Joe and Iris, Barry pleads Dr. Wells to find a way to restore his powers. Wells suggests “jump starting” Barry’s latent powers by striking him with a force similar to the particle accelerator-fueled lightning bolt that gave Barry his speed. But with in the STAR Labs building, Barry thinks that maybe he should talk to him first. Barry confronts Farooq, who demands to see Dr. Wells. Farooq senses the familiar energy readings off of Barry, and identifies him as the Flash. Farooq electrocutes Barry and flees. Dr. Wells tells Cisco and Snow to get Barry to Cisco’s treadmill so they can jumpstart Barry. Wells says he must confront Farooq on his own. However, he goes to Girders cell and makes a bargain with him. If Girder kills Farooq for Wells, then Wells will set him free.
At the precinct, Clock King makes his demands to the Central City Police. When he grows increasingly erratic and dangerous when the police don’t meet his demands, Eddie Thawne tries apprehending him. The man moves too quickly though, and shoots Eddie down. Clock King ties a tourniquet on Eddie’s arm, giving him some time to survive.
As Farooq continues to hunt down Barry and the power inside him, Girder attacks him. As they two battle, Barry and Snow are afforded the time to move to the treadmill. While Snow has doubts that Barry will survive the process, Barry tells her that they have to try. The experiment doesn’t give Barry his powers back, but it doesn’t kill him either. As they move, Barry and Snow find Girder lying on the ground, electrocuted to death by Farooq.
Snow takes Barry into another room to test his blood. Wells enter the room and admits that he freed Girder to help save Barry. Barry criticizes Wells for sacrificing Girder’s life to preserve Barry’s, saying that Wells coldly uses people as his pawns to further his own agenda. But Barry’s cells start rapidly regenerating, showing that his powers are—ironically enough—coming back slowly. Farooq enters the room however, and demands to see Harrison so that he can have his revenge. He is about to kill Barry, but Dr. Wells enters the room and tells Farooq to kill him instead. Farooq electrocutes Wells. The sight kickstarts Barry’s speed powers back to full maturity. With his super speed restored, Barry fights Farooq. Farooq tries sapping his energy again, but Barry is too strong this time. His immense power “overloads” Farooq, killing him. Snow deduces that Barry’s cells are now producing more energy than ever before. As Wells notes, Barry finally “kicked it up a notch.”
When the Central City Police finally deliver an escape helicopter for Clock King, Clock King grabs Iris as his hostage for when he boards his helicopter. Joe convinces Clock King to at least let Iris say goodbye to Eddie before taking her away. But Iris takes Eddie’s gun and shoots King down.
Barry races to the precinct, but the situation is under control. The police have taken King into custody while Joe and Iris recuperate. He heads back to STAR Labs, where he apologizes to Dr. Wells for calling him cold. Wells says that Barry’s judgments weren’t wrong, but says that he does what he does because he cares about the greater good. Barry then goes to the hospital to see Eddie, who is recovering from the shooting.
Barry then changes into the Flash and sees Iris in the hospital’s lobby. He apologies for “not being there” for Iris during the hostage situation, but promises that he’ll never be late for her again.
Back in STAR Labs, Dr. Wells opens another log in his time chamber. Dr. Wells notes that Barry’s compassion for the people he cares about will unlock his true potential. The Crisis newspaper headline from the future reappears, confirming that Well’s future “remains intact.” Wells then goes to STAR Labs’ morgue and extracts blood from Farooq’s corpse. Knowing that Farooq could steal the Flash’s powers, Wells says that he plans to find out how Farooq could achieve such a feat, and then replicate the process for himself. Could Wells distill the Flash’s powers and try using them, transforming himself to a Reverse Flash? Hopefully we’ll find out after next week’s Flash/Arrow crossover.