Supergirl Trailer: The Legion of Superheroes Assemble!

The Legion of Superheroes will finally assemble on Supergirl Season 3 Episode 10, and it looks set to be one of the best episodes of the series to date. 

Reign won the battle against Kara on Supergirl Season 3 Episode 9, so she will be riding high after putting her world-killing abilities to use. 

But for Mon-El, this will push him to reach out to the Legion of Superheroes for help. It also means it will give the Daxam native time to don a superhero costume of his own. 

Have a look below to see what we're talking about here. 

The official trailer The CW dropped on Wednesday for "Legion of Superheroes" shows the characters joining forces to try and find a way to wake Supergirl up from her slumber. 

Reign will not stand for Kara returning to her superhero ways, but will the Legion of Superheroes be able to get the upper hand on the villain?

This storyline also presents an interesting plot for the DEO. How would they react to the loss of Kara/Supergirl?

There's no way the show would kill off its titular character, but it sure is fun to see the desperate measures everyone will go to in order to save her. 

Have a look at the supersized teaser below and join us in the comments with your thoughts on it. 

Remember you can watch Supergirl online right here via TV Fanatic. 

Supergirl returns to The CW January 15.