Get ready for the epic four-way crossover with Supergirl, Arrow, The Flash and DC’s Legends of Tomorrow. Barry Allen (GRANT GUSTIN) and Iris West’s (CANDICE PATTON) wedding brings the gang together, but things go awry when villains from Earth-X attack the ceremony. All of the superheroes band together, with help from their super friends like Citizen Cold (guest star WENTWORTH MILLER), The Ray (guest star RUSSELL TOVEY), Felicity Smoak (EMILY BETT RICKARDS) and Alex Danvers (CHYLER LEIGH) to take on their most formidable villains yet. Earth’s mightiest heroes – Green Arrow (STEPHEN AMELL), Supergirl (MELISSA BENOIST), The Flash (GUSTIN) and White Canary (CAITY LOTZ) – lead their teams into battle to save the world.
Kara's heart soars as she takes to the skies as Supergirl to fight crime.
Based on the DC character, Supergirl decides to embrace her superhuman abilities and become the hero she was always meant to be.