Taking place six months after Barry left, things have settled into a new normal: Barry is still gone after walking into the Speed Force prison and Team Kid Flash/Team Vibe is trying to carry on the work of keeping Central City safe without its most experienced superhero.
Iris has seemed to have locked away her heart and to guard herself from her feelings for Barry and any possibility of his return. He was gone and that belief allowed her to move forward and “keep running,” as he asked of her.
Team Vibe was doing its best to keep Central City safe, but their Meta capture rate suffered without The Flash. While the team may not be as successful overall, together they used wit and teamwork to capture Peek-a-Boo. Cisco and Wally complement each other with their powers, while Iris proved herself invaluable as the person behind the computer.
Cisco gets help from Caitlin Snow and the Arrow-verse on a solution to bring Barry back. She’s seemingly cured of her Killer Frost problem, but still in exile, bartending and hanging out with shady characters who don’t seem like they’re totally into the Team Flash saving the world.
Barry’s returns, but in bad condition. There was a consequence to his time in the Speed Force, and I hope that even though he appears cured that some side effects remain. All while Samurai wanted to face-off against the Flash.
Team Flash is unable to beat Samuroid and sincerely believe he’ll make good on his promise to destroy Central City. And so, Iris, taking her father’s advice to have some faith to go along with her strength to an extreme, tells the Samuroid to take her hostage because he believes The Flash will come for her.
Barry pushes through his brain mush to take Cisco’s bright new costume and pursue the Samuroid through a wind farm for another really fun action scene. He saves Iris, reveals the Samuroid to be a robot, and confirms to Iris that yes, he’s back. And he’s not just back, he’s lighter and happier, and not interested in dwelling on dark things anymore!
The final moments welcomed the Mechanic and the Thinker as the villains of Season 4. They must not have been able to get Barry out of the Speed Force themselves, so they forced the hands of his friends who could. Their agenda remains unknown, but their abilities and threat are definitely nefarious and going to challenge Team Flash.