Crisis on Earth-X

Part 1 A Nazi regime rules the parallel world of Earth-X, where an archer known as Dark Arrow is the Führer and leader of the cabal known as the New Reichsmen. He seizes a temporal gateway from the Freedom Fighters, which enables travel to other universes. On Earth-1, Barry Allen and Iris West's friends, including Kara Danvers and Alex Danvers from Earth-38, come to Central City for Barry and Iris's wedding. Harry Wells, Cisco Ramon, and Caitlin Snow develop a serum to separate the Firestorm matrix from Martin Stein and Jefferson Jackson. However, Jefferson is reluctant to give up being Firestorm, while Stein is thrilled at the prospect of being able to live a normal life with his family. Oliver Queen re-proposes to Felicity Smoak, but she is hesitant about marrying him. The wedding ceremony is interrupted by invaders from Earth-X led by Dark Arrow, his Kryptonian wife Overgirl, and the Earth-X analog of Prometheus. After Alex and Sara Lance capture Prometheus, the Nazis retreat. Dark Arrow and Overgirl, who are doppelgängers of Oliver and Kara respectively, discuss their next step with Eobard Thawne, Barry's speedster nemesis who was previously presumed dead. Part 2 In S.T.A.R. Labs, Prometheus reveals himself as Tommy Merlyn's Earth-X doppelgänger, and taunts Oliver before taking a suicide pill out of loyalty to the Führer. Harry reveals that, through his exploration of the multiverse, he discovered that Earth-X is a dystopian world where the Allied forces lost World War II. Dark Arrow, Overgirl, and Thawne steal an experimental sub-light generator, the Prism, from a research company. Oliver's team, along with Harry, Killer Frost, Cisco, and Mick Rory, are held captive at S.T.A.R. Labs after the Nazi forces occupy it. Oliver, Barry, Sara, Martin, Jefferson, and Alex are taken to a concentration camp on Earth-X, while Kara is moved to S.T.A.R. Labs. Overgirl is dying from disproportionate solar irradiance in her heart, and Dark Arrow plans to use the Prism, powered by S.T.A.R. Labs' particle accelerator, to create artificial red sunlight that can weaken both Karas' invulnerability, allowing Thawne to transplant Kara's heart to Overgirl. Part 3 In the concentration camp, the heroes are rescued from execution at the hands of SS-Sturmbannführer Quentin Lance by Ray Terrill and Leo Snart, Leonard Snart's doppelgänger. Thawne prepares to operate on both Overgirl and Kara, and Iris and Felicity work to rescue their friends at S.T.A.R. Labs. General Winn Schott, the commander of the Freedom Fighters, is determined to strand Dark Arrow and Overgirl on Earth-1 by destroying the temporal gateway. While posing as Dark Arrow, Oliver discovers that the Nazis possess a doomsday device in the form of a timeship called Wellenreiter, a militarized equivalent of the Legends' Waverider. Oliver allows the timeship to enter Earth-1 to avoid jeopardizing his cover, but he is ultimately exposed when he refuses to kill Felicity's Earth-X doppelgänger, a concentration camp prisoner. The heroes struggle against both the Freedom Fighters' Red Tornado, deployed by Schott as a failsafe, and the Nazi forces, and Martin opens the gateway at the cost of being mortally wounded. Part 4 The heroes return to Earth-1, and Iris, Felicity, Kara, and the others are rescued by the returned heroes and the Waverider crew. Jefferson is also affected by Martin's injuries, so Martin uses the serum to separate the Firestorm matrix, dying from his wounds. Jefferson tells Martin's family of his fate; they, along with the Legends and Barry's team, are devastated by Martin's death. His death spurs the heroes to declare war on Earth-X's Nazi forces. When the Nazis attack Central City, the heroes counter their assault. Harry, at the helm of the Waverider, destroys the Wellenreiter after the heroes disable its shield. Barry spares Thawne and allows him to escape; Thawne vows to return. During the battle with Kara, Overgirl's solar radiation goes nuclear, and Kara carries her into space, where her body explodes, killing her; Oliver, despite giving Dark Arrow a chance to stand down, kills his grief-stricken doppelgänger soon after. After Martin's funeral, Kara and Alex return to Earth-38, Ray returns to Earth-X, and Leo decides to temporarily join the Legends. John Diggle, an ordained minister, officiates Barry and Oliver's weddings with Iris and Felicity, respectively. ==Cast and characters==

Main and recurring Only those who appeared in multiple episodes are listed on the table. Despite being credited, Katie McGrath and Odette Annable do not appear in the Supergirl episode, and David Ramsey and Katie Cassidy do not appear in the Arrow episode. Guest Supergirl • Jesse L. Martin as Joe West • Keiynan Lonsdale as Wally West / Kid Flash • Jessica Parker Kennedy as a caterer • Danielle Nicolet as Cecile Horton • Patrick Sabongui as David Singh • William Katt as the minister Arrow • Colin Donnell as Tommy Merlyn / Prometheus (Earth-X) The Flash • Paul Blackthorne as SS Sturmbannführer Quentin Lance (Earth-X) Legends of Tomorrow • David Ramsey as John Diggle • Susanna Thompson as the Wellenreiters A.I. (uncredited) ==Production==

Development and filming Planning for the yearly Arrowverse crossover began in December 2016, with Arrow showrunner Wendy Mericle saying, "We actually sort of do, believe it or not, have a concept for what we want to do for next year's crossover. It's crazy". "Free Stress Test" by Professor Murder, "Justice" by Misun, "All Eyes on You" by St. Lucia, "By the Stream" by Tom Hillock & Nicolas Boscovic, "Love Is Emotional" by Neil Finn, "String Quartet No. 62 in C Major, Op. 76, No. 3, Hob. III:77, "Emperor": II. Poco Adagio, Cantabile" by Kodály Quartet, and "Runnin' Home to You" (from the musical crossover episode "Duet") performed by Melissa Benoist are heard in the first part of the crossover but not included in the soundtrack. == Marketing ==

Comic artist Phil Jimenez created a custom cover for the event, which invokes the cover design of the Justice League of America #207, the 20th annual Justice League of America and Justice Society of America crossover. Promotional trailers for the event were released throughout November, before the full trailer was released on November 20. ==Release==

Broadcast The crossover began with Supergirl and Arrow on November 27, 2017, and concluded on The Flash and Legends of Tomorrow on November 28, all on The CW. Arrow, which normally aired on Thursdays at 9pm, moved to Monday at 9pm for the crossover and did not air an additional episode on November 30. Pedowitz stated that they decided to have the crossover occur over two nights, as opposed to the four nights of "Invasion!", because The Flash and Legends of Tomorrow were already paired together on The CW's schedule, and "it would be better and tighter in terms of storytelling to make it like a two-night, four-hour miniseries. We thought this was a tight, concise way of doing it". Guggenheim added, "We're really approaching this big four-part event as two back-to-back two-hour movies, and I think when you look at it through that lens, it becomes less important for the Supergirl episode to feel like a Supergirl episode and the Arrow episode to feel like an Arrow episode, which was always our approach in the past". Guggenheim tried to get "Crisis on Earth-X" released as some kind of "single, seamless, no act breaks" movie, with the possibility of even shooting up new footage, though this was not possible due to union rules. Home media All four episodes and the behind-the-scenes featurette "Inside the Crossover: Crisis on Earth-X", were released on Blu-ray and DVD in Region 1 along with the rest of Arrows sixth season on August 14, 2018, The Flashs fourth season on August 23, Supergirls third season on September 18, and Legends of Tomorrows third season on September 25. The four episodes were released together on a separate DVD on September 3, 2018, in Region 2, and September 5 in Region 4. ==Reception==

Ratings "Crisis on Earth-X" was released on The CW in four parts on November 27 and 28, 2017. The crossover was viewed by an average audience of million viewers per episode. Part one, the second lowest viewed episode, was released to an audience of 2.71 million viewers. It was followed by the lowest viewed, Part two, with only 2.52 million. Schedeen gave the Supergirl episode an 8.1 out of 10. While he felt that the Supergirl episode "clearly isn't in much of a hurry to get where it's going", Schedeen said it did "prove to be a very entertaining start to the crossover." Ultimately, the episode "did, however, make the most of this massive pairing of heroes, delivering an endless stream of banter and character drama before transitioning into an epic battle royale. There are certainly worse ways to kick off a crossover." Schedeen gave the Arrow episode a 7 out of 10, saying that the episode "struggled to find that balance between character drama and plot progression, as well as in establishing stakes big enough to support such a massive crossover in the first place. But for all its flaws, at least this episode still included some entertaining moments and a generally strong portrayal of its twisted villains." Schedeen awarded The Flashs episode a 9.2 out of 10, noting that while part 1 had "a slow start" and part 2 gave "a fairly underwhelming follow-up... the crossover finally seemed to click" in part 3. Scott Von Doviak at The A.V. Club gave the episode a "B+" rating, stating "Even a lesser installment like this one features the spectacle of the Flash and The Ray battling the Red Tornado, as well as the appealing non-superpowered Nazi-fighting team of Iris and Felicity. For the most part, I've felt like a kid coming home with a fresh stack of comics, and I can think of no higher praise than that." Mike Cecchini of Den of Geek gave it 4 out of 5 stars. He wrote that while mirror universe Nazis' don't make for the most nuanced of villains, and when you're using concentration camp imagery, well, you'd better make sure you're not being exploitative," The Flash episode "completely embraces its lunacy in ways that I don't even think those first two chapters dreamed of." Legends of Tomorrow episode Schedeen gave the final episode an 8.5 out of 10 rating. The episode "didn't have quite the urgency it needed during the final showdown between good and evil," but "did make the most of Professor Stein's heroic sacrifice and its emotional fallout." Oliver Sava of The A.V. Club gave the episode an "A" rating, stating "No piece of live-action superhero media has captured the feeling of a comic-book crossover event like Crisis On Earth-X. With a huge cast of characters, a major death, and a final scene taking big heroes in bold new directions, Crisis delivers the thrills, the twists, and the inspiration that should come from a superhero story with this massive scope." Jim Dandy from Den of Geek rated the episode 5 out of 5 stars. He wrote, "This year's was an objectively wonderful hour of DC television, but it also moved the season's story along for Legends in a meaningful way, and provided significant character development for Jax and Sara. It gave Franz Drameh and Victor Garber a chance to stretch their acting wings, and it closed out a timely, wall-to-wall entertaining four hours of television." Colliders Carla Day gave the Legends episode 5 stars out of 5, saying the crossover was "leaps and bounds better than any of the previous crossovers." She went on to say that "It set the standard high for all future crossovers in the story, character interactions, and fight scenes." == Notes ==