After last week’s absence, The Flash strikes back in a big way, bringing Arrow to his world for the very first part of the crossover, "Legends Of Today".
Barry’s training to get faster, but Caitlin and Wells tell him he doesn’t, so he leaves to meet Patty, but Harry has something in mind. A ship’s captain has picked up a guy from the sea with a whole lot of knives on him. He’s cuffed, but transfers his cuffs to the Cap, kills everyone and gets on his way, planning to sacrifice Hawkgirl. Joe examines the mass-murder, with Barry knowing it was just one person and Patty thinking of a metahuman. Kendra takes Cisco to the closed coffee place she works for dinner, when the bad guy from the doc appears and wants to take her. Thankfully, Barry saves the two of them fast and explains the situation at STAR Labs, wanting them to go over to STAR City. Cisco has his doubts, but Barry insists since team Arrow knows mystical stuff better. Meanwhile at Star City, Damien Darhk and his ghosts are about to steal a chemical bomb, when the gang appears. They get the ghosts gunless and fight, but Darhk almost kills Oliver, with The Flash saving him at the last minute and asking for their help to protect a friend.
They all gather at the lair for chit-chat with Cisco judging their wiring, before Kendra is introduced and Barry draws the bad guy’s face. Felicity finds a photo of him from 1975 and Oliver interrogates Kendra, with everyone telling him to slow down. At STAR Labs, Wells is working on a serum he had to make Jay faster, but Caitlin jumps in to help him with a new version of it. At Star, they all gather at Oliver and Felicity’s and catch up, when Cisco tells Barry about his vibe of Kendra as Hawkgirl. The bad guy comes in throwing knives at everyone, with Barry saving them but getting hit, only for Oliver to be brought to the ground as well. It’s Thea’s arrows that get him hit and thrown down from the balcony, and everyone’s angry at her for doing that. However, when they look down for him, he’s nowhere to be seen. At the Lair, Cisco tells Kendra about his vibe, when the lights go out so Malcolm and the League can make an entrance.
At STAR Labs, Jay was called to test the serum but is furious and wants nothing to do with it. Malcolm tells everyone the bad guy is named Vandal Savage and he seems to be an immortal, which gets Kendra outside with Cisco following her, before winged guy takes her away. As they look for her, she’s taken to a rooftop and is asked to emerge, as the guy calls her Priestess Shayara (or something) and himself Khufu. The Flash and Green Arrow get into an epic fight with him and eventually get him down with one of the former’s lightnings. At STAR, Wells has completed the serum and Cailtin’s worried, Patty comes in mentioning she remembers him from the Dr. McGee robbery and thinks he’s got a gun, so shoots him. When Caitling realizes what went down, she asks to call Joe. At the lair, Khufu is chained and says he and Kendra are soulmates, killed by Savage in every life, as it makes him more powerful. Malcolm appears once again to say he’s left town to get the Staff Of Horus, a powerful ancient weapon, while Felicity looks it for in museums.
Joe sends Patty away from STAR Labs and they need Jay to help him. Khufu wants Kendra to jump off a rooftop to get her wings and so she does, but Barry saves her at the last minute. Oliver confronts him about letting her have her own part and realizes the weapon should be in Central city where she was drawn. Jay takes the speed serum and removes the bullet from Harry, with Caitlin closing him. Kendra talks with Cisco on the roof and she’s now more ready to embrace her inner self. The Flash and the Green Arrow arrive at the church with the item, only Savage already has it and they fight. Kendra jumps off the building and her wings come out. Vandal blows the church down and Barry speeds out with Oliver, while Cisco calls Kendra Hawkgirl. Wells thanks Jay, who doesn’t want the serum anywhere near Barry. Oliver calls Diggle to bring them all to Central and Khufu agrees it’s their best chance. With Laurel already there, Oliver and Barry go to Jitters, where they walk by a young boy, who’s mother is Oliver’s ex, the one his mother paid to lose their baby.
And that’s all for now. Make sure to tune in on The CW again tonight for the follow-up to "Legends Of Today" and second part of the crossover on Arrow.