Reign was released on National City in the Season 3 midseason finale of Supergirl, forcing Kara to admit the unthinkable – the supervillain is more powerful than her. This realization led to the unceremonious pummeling of Supergirl, who, according to a newly released synopsis for the series’ return, will need the aid of Brainiac 5 to regain consciousness and heal her injuries.

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Brainiac 5 is a member of the Legion of Superheroes, a vigilante band of heroes from the 31st century. First introduced in Action Comics #276 in 1961, Brainiac 5 was created by Jerry Siegel and Jim Mooney. Brainiac 5 has a superior intellect and impressive memory. The character will be brought to Kara’s side by Mon-El, whose own adventures in the future helped him to found the Legion of Superheroes.

The synopsis reads:

"Legion of Superheroes"

"MEET THE LEGION – Struggling to heal from her injuries inflicted by Reign (Odette Annable), Supergirl (Melissa Benoist) remains in a dreamlike state, unable to be reached. Mon-El (Chris Wood) recruits one of the Legion members, Brainiac-5 (guest star Jesse Rath), to try to bring her back. Meanwhile, Reign continues her rampage on the city so the DEO teams up with the Legion of Superheroes to try to stop her. Jesse Warn directed the episode written by Derek Simon & Eric Carrasco (#310). Original airdate 1/15/18."

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Returning Monday, Jan. 15 at 8 p.m. ET/PT on The CW, Supergirl stars Melissa Benoist as the Girl of Steel, David Harewood as Martian Manhunter, Mehcad Brooks as Jimmy Olsen, Chyler Leigh as Alex Danvers and Jeremy Jordan as Winn Schott, with appearances by Calista Flockhart as Cat Grant and Tyler Hoechlin as Superman.