‘Flash,’ ‘Arrow,’ ‘Supergirl,’ ‘Legends Of Tomorrow’ Crossover Spoilers & Promo: Kara Meets Barry’s Super Friends; What To Expect From Lillian Luthor

A new promo was released for the upcoming four-way crossover between The CW's "The Flash," "Arrow," "Supergirl," and "Legends of Tomorrow." The new clip may be short but it sure built up the hype as Barry (Grant Gustin) introduces Kara a.k.a. Supergirl (Melissa Benoist) to his other super friends in Greg Berlanti's TV multiverse.

In "The Flash," "Arrow," "Supergirl," and "Legends of Tomorrow" promo, Kara was introduced to the Green Arrow (Stephen Amell), White Canary (Caity Lotz), Firestorm (Robbie Amell), and The Atom (Brandon Routh), among others, TVLine listed. The superheroes will fight DC Comics' Dominators, an alien race that wants to use Earth's meta-humans to other, more sinister purposes. Watch the exciting promo for "The Flash," "Arrow," "Supergirl," and "Legends of Tomorrow" crossover below.

Executive producer Marc Guggenheim revealed that the special four-way crossover will kick off after the Nov. 28 episode of "Supergirl" Season 2. The Kyptonian will be "going over to the crossover" and straight into a story that has three main parts: a beginning, middle, and an end. Guggenheim clarified that "The Flash" is the beginning, "Arrow" is situated in the middle, and "Legends of Tomorrow" will have the ending. The Girl of Steel is "very much a part of the whole thing."

The Dominators are aliens that possess mind-control abilities. According to Entertainment Weekly writer Jeff Jensen, this mind-control aspect of the extraterrestrials opens up the possibility of the superheroes fighting each other on "The Flash," "Arrow," "Supergirl," and "Legends of Tomorrow" crossover.

Wild Dog (Rick Gonzalez) will clash with The Flash and Supergirl because he views the two's superhuman abilities as a possible threat to the world, Parent Herald previously reported. Oliver, meanwhile, will have a hard time letting Kara into the fold.

Expect Sara a.k.a. White Canary and Diggle (David Ramsey) to welcome the Girl of Steel warmly on "The Flash," "Arrow," "Supergirl," and "Legends of Tomorrow" crossover, though. Check out photos from the upcoming crossover on the link below.

Peek inside DC's EPIC crossover featuring the casts of #Arrow, #TheFlash, #LegendsOfTomorrow and #Supergirl: https://t.co/6EaN6b1JTb pic.twitter.com/oCPqOxCO53

— Entertainment Weekly (@EW) November 12, 2016

In other news, "Supergirl" Season 2 recently introduced a new villain called The Doctor, who is actually Lillian Luthor (Brenda Strong), Lex's mother and Lena's (Katie McGrath) adoptive parent. Lillian is the leader of the anti-alien terrorist organization Project Cadmus.

"Supergirl" executive producer Andrew Kreisberg told EW that Lillian is "not somebody to be messed with" and possesses "a great deal of power and scientific know-how." This does not bode well for Kara, of course.

What do you think about "The Flash," "Arrow," "Supergirl," and "Legends of Tomorrow" crossover? Share your thoughts below.