Invasion! (DC's Legends of Tomorrow)


 * For episodes of the same name, see Invasion!.

"That's what you've all proven here. Meta-humans or not, superpowers or not, you are Earth's mightiest heroes."

- Kara Danvers

"Invasion!" is the seventh episode of the second season of DC's Legends of Tomorrow, and the twenty-third episode overall. The episode is the fourth of a four-part crossover with the eight episode of the season two of Supergirl, eighth episode of the third season of The Flash and eight episode of the fifth season of Arrow. It aired on December 1, 2016.

Synopsis
After learning the Dominators' plan for the world, the Legends must work together with The Flash, Supergirl and Green Arrow to kill them once and for all. Meanwhile, Stein figures out, with the help of others, how the team can terminate the Dominators, but is distracted by the aberration he realizes he created in 1987.

Production
Preparation ran from September 16 until September 26, 2016. Shooting ran from September 27 until October 12, 2016, with a break for Canadian Thanksgiving on October 10.

Trivia

 * This is the first crossover episode of Legends of Tomorrow.
 * When Agent "Glasses" Smith tells the team about the Dominators, he calls them Xenomorphs, a reference to the Aliens film franchise.
 * When Ray looks at Kara, he tells Felicity that she reminds him of his cousin. This is a reference to the fact that Brandon Routh portrayed Superman in the 2006 film, Superman Returns.
 * The Dominators visited Earth in 1951, landing in Redmond, Oregon. Oregon also happened to be U.S. state where the potential existence of alien life was introduced to the TV show "The X-Files" during the pilot episode back in 1993.
 * It's revealed in this episode that Barry is the winner of the duel between him and Oliver at the end of "The Brave and the Bold".
 * The name of Martin Stein's daughter is revealed as Lily Stein.
 * It's revealed in this episode that Cisco can "vibe" another person with him without tech equipment.
 * Kara calls the superheroes in Earth-1 "Earth's Mightiest Heroes". This is the nickname of Marvel's Avengers, who are in charge of protecting the Earth from superhuman threats.
 * When Felicity is linguistically challenged after the time jump at one point she says "Darmok and Jalad at Tanagra" really fast. This is a reference to the well known Star Trek TNG episode "Darmok" S05E02, in which the aliens speak entirely in metaphors.
 * Another Star Trek reference is made when Cisco says "set your phasers to stun."
 * This episode marks the first official appearance of The Flash on Legends of Tomorrow but his voice was heard in "Shogun" and "Abominations".
 * When Mick told Barry that "when you've got a crew you gotta take a hit for the rest" it bears a resemblance to when Snart told the Legends back in Pilot, Part 2 that "if you take out one of his crew, you pay the price" - it shows that Mick does indeed have a similar sense of honor to Snart.
 * In the original draft of the episode, Lynda Carter was intended to play the new POTUS of Earth-1; acting as a doppelgänger of Olivia Marsdin, who is the POTUS of Earth-38. At the suggestion of the studio, the role was changed, as they thought it would be too confusing. Eventually, Lucia Walters got the role, and an original character was created.
 * When Nate, Amaya and Mick land in Oregon in 1951 to capture a Dominator, Mick starts burning it with his Heat Gun and he says: "Squeal, you pig!". This is possibly a reference to a famous quote from the film Deliverance.
 * When Kara leaves after talking to Agent Smith about his reassignation to Antarctica, Nate tells him that next time he should be "a little nicer to strange visitors from another planet". This could be a reference to the Supergirl first season episode "Strange Visitor From Another Planet" and also the tagline from the original Adventures of Superman TV series.