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Barry's birthday party is ruined by the return of Bloodwork, who has plans beyond taking over the world involving Kid Flash and the multiverse. In order to save his friends and all reality, Barry Allen will have to turn to someone else... who has become something else.
Zero Hour (Bloodwork's plan to "fix" the Multiverse mirrors Parallax's mad plan.) and the previous annual The Flash/Arrow crossovers.
This episode takes place on March 14, 2023. This means that it must occur before the last three episodes chronologically. However, that doesn't fit the timeline of the previous episodes, with Allegra telling Chester she loves him, which first occurred in 908 on April 5, 2023.
Bloodwork says he just escaped from prison, However, his escape came during the 2022 Earth-Prime comic series, meaning that he should have been on the run for at least two and a half months.
Stephen Amell slips easily into the role of Oliver Queen one more time, but with a little more humor given the knowledge he has now as The Spectre.
The special effects are fairly solid this time around.
The title is a pun based on a lyric from the Lesley Gore song "It's My Party."
This episode continues the tradition of the annual Arrow/The Flash crossover taking place on the 9th episode of the season.
The episode features a special title card, in the middle of the episode.
This episode was directed by Danielle Panabaker, who plays Khione.
This episode marks the first time Barry's birthday party has been celebrated on-screen.
This is the first episode in which David Singh and Kristen Kramer have appeared together, despite Kramer serving directly under Chief Singh.
Barry makes reference to "the Hall" as a place to display Oliver Queen's bow. This seems to be a nod to the Hall of Justice which was established (without being named) at the end of Crisis on Infinite Earths.
Chester exclaims "Holy Duane Jones!" when encountering the Bloodwork zombies. This is a nod to actor Duane Jones, who played the lead role of Ben in the original Night of the Living Dead.
Oliver tells Diggle that his brightest days are ahead of him. This is a nod to the Green Lantern oath.
Wally recommends a drink made of dried sendru and honey to help Iris fight morning sickness.
The necklace Chester made Allegra contains a facial transmogrifier.
To stop Bloodwork's powers from metastasizing inside a breach. a massive ultraviolet pulse is required.
(After Wally refuses to work with Bloodwork.)
Bloodwork: I understand your hesitation. No one has ever really believed in you, have they? You have been cut down your entire life, forced to watch your mother suffer. It is a pain that I know all too well. My mother was diagnosed with HLH, and I couldn't save her either, Wally. I had to watch her die. And we have that in common. Then you understand what it is that I'm trying to do... That it's about more than just stopping death. It is about ending the suffering that we have both endured, that, together, we can create a Multiverse where no one has to watch their loved ones die...
Ollie Queen: Oh, Barry, Barry, Barry... what have you done this time?
(Wally hugs Ollie, who, for once, returns it.)
Ollie: Okay. Let go. Barry, let go.
Barry: Wait. If you're here, that means I'm really...
Ollie: You're dead. Otherwise, why would I let you hug me that long?
Barry: But when we fought the Red Death, she thought she escaped from her timeline into an alternate one -
Ollie: She is from Earth-4125.
Ollie: I've had a bit of time on my hands...
Barry: I fight some random mad scientist. I get three extra years to live. You know everything now, right, Oliver? Tell me, how is it right I'm alive and they're dead? How's that fair?
Ollie: Life is a lot of things, Barry. Fair isn't on the list.
Ollie: You still would have been a hero.
Barry: Maybe. But you made me a better one.
Ollie: You made me a better man.
(Ollie gets ready to leave the bar.)
Ollie: Okay, Mr. Allen, I think that I have done enough to upset the cosmic order for one night. Can you get this?
Barry: Are you kidding? You're a billionaire.
Ollie: Well, you... you can't take it with you.
Cecile says that the first time Barry turned 30, the team was too busy fighting Cicada to celebrate.
Chester is in charge of the entertainment for the party, Allegra and Cecile took care of the decorations, and Khione is said to be out getting the cake.
The party attendees include Cecile, Chester, Allegra, Kristin Kramer, David Singh, Joe West, Wally West and John Diggle.
Wally West appears for the first time since 614.
Kristin Kramer and David Singh argue over who is the better Captain.
Diggle gives Barry Oliver Queen's bow, which ARGUS recovered from National City. Somehow, it wound up there after being presumed lost on Earth-38.
It has been three years since Oliver Queen died saving the multiverse.
Diggle makes reference to Caitlin's apparent death.
Barry tries to refuse it, but suggests maybe they could display the bow in "The Hall."
Chester makes Allegra a necklace that should hide her face whenever she is using her powers for their one-month anniversary.
Wally is still studying with Bhikkhuni Amala in the Himalayas.
Wally tells Barry that after Iris told him about the Red Death, he began projecting his consciousness into the Speed Force to explore alternate timelines, hoping to find another version of himself who already found enlightenment whom he could learn from.
Wally says there's baggage he needs to get past, but doesn't talk about it more when Barry asks what his issue is.
Bloodwork is revealed to have put his blood into the champagne and cider for Barry's birthday toast. Everyone except Chester (who doesn't drink), Iris (who shares Nora's healing factor) and Barry and Wally (whose powers protect them) are infected.
Bloodwork reveals that his plan this time is to target Wally and break his mind through their connection then use his powers to travel the multiverse and spread his tainted blood around multiple Earths.
Bloodwork sees that the real reason Wally was exploring the alternate timelines was to try and find somewhere his ex-girlfriend, Jesse Quick, was still alive.
Chester flees to his lab and barricades himself inside.
Iris is able to lock herself inside the Time Vault, but is slowly losing control of herself.
Bloodwork gets Wally to kill Barry by vibrating his hand through his chest.
Barry wakes up in Purgatory (which looks like Lian Yu island) and is greeted by Oliver Queen.
Oliver Queen appears for the first time since A810.
Oliver confirms that he created Earth-Prime so that all his allies would have a single Earth to protect together. He also created the new Multiverse.
Red Death is confirmed to be from Earth-4125 rather than an alternate timeline.
Khione says she felt a presence calling her, telling her she was needed back at STAR Labs, while she was waiting in line for the cake. This presence is later revealed to be Oliver Queen.
Oliver resurrects Barry and manifests, temporarily as Green Arrow one more time.
Khione is only able to safely thaw out John Diggle after removing Bloodwork's blood from his system.
John Diggle joins the fight against Bloodwork.
Barry is able to reach Wally and help him fight Bloodwork's control.
Barry and Team Flash learn that a new multiverse exists.
Ollie reveals that Khione's powers come from a connection to the natural world, which allowed her to expel Bloodwork's unnatural cells from the rest of the team.
Wally decides to stop exploring the multiverse and look for the answers he seeks within.
Ollie gets a chance to stay goodbye to John Diggle that he didn't during the Crisis.
Ollie confirms that he is keeping an eye on Felicity, Mia and William, but that part of the rules of his being The Spectre are that he can't make contact with his family. He was, however, able to bend the rules for Diggle since he was there at the crisis point.
Diggle confirms he is watching over Ollie's family too, telling him that William has started college and Mia can already climb a salmon ladder scaled to her height.
Oliver confirms that there are Flashes on the other Earths, but Barry is still his favorite.
Ollie and Barry have their traditional post-team-up drink before Ollie disappears.
O'Shaughnessy's Bar in Keystone City
The Bottom Line
Easily the best episode of this short season so far. Ignoring the lore involving the larger Arrowverse setting and all the nods to past episodes, Bloodwork is allowed to be far smarter than any villain in recent memory. This was a flashback to better days, no pun intended, and it is a shame that more of Season 9 couldn't be like this.