The Legion of Super-Heroes springs to action as Reign attacks National City in the trailer for Supergirl season 3's return in 2018. Now that the origins of the team have been explained by Mon-El (Chris Wood) and Imra Ardeen/Saturn Girl (Amy Jackson) to the DEO and Kara (Melissa Benoist), it looks like these Super-Heroes are going to have to step up to the plate, what with Supergirl now in a coma following her intense battle with the World Killer Reign (Odette Anabelle).

As was revealed in the Supergirl season 3 midseason finale "Reign", Kara was the inspiration for the Legion, as well as their mission to safeguard peace and ensure that justice is served. Given this, it makes sense that the (accidentally, time-traveling) squad would be willing to suit up in the 21st Century to temporarily carry out Kara's responsibilities of keeping National City safe, while the Girl of Steel is recuperating from her battle wounds.

Related: How Supergirl Introduced the Legion of Super-Heroes

The CW has now posted the trailer for Supergirl's return in 2018 online (see the video in the space above), via an episode fittingly titled "Legion of Superheroes". This season's big bad is shown wreaking havoc across National City here, and even making a pit-stop at CatCo. Meanwhile, we hear Kara's voice in the background, almost like she's willing herself to wake-up while she's in a coma, saying "I have to wake up" as we see her unconscious body inside a recuperating tank. However, the big takeaway here is the split-second shot of three hands wearing Legion of Super-Heroes rings, united in their cause.

Legion of Superheroes Ring Supergirl

It would appear that these three hands belong to Mon-El, Imra, and Braniac 5 (Jesse Rath), indicating that the three are gearing up for battle in an effort to contain Reign and give Kara a bit more time to heal, until she's ready to get back on her feet once again. It's not yet clear how many other members of the Legion of Super-Heroes will be appearing on the shown in the future, be they Cosmic Boy, Lightning Lad, or even Matter-Eater Lad. Still, the idea of the series potentially setting up a small screen adaptation of  The Great Darkness Saga comics run is reason enough for Supergirl fans to be excited for now.

Unfortunately, we have to wait for a few weeks before we get the brand new episode teased in the trailer, as Supergirl has just entered its regular midseason break, having up its first half of its third season with Monday night's episode.  The rest of the Arrowverse shows (DC'S Legends of Tomorrow, The Flash and Arrow) will all follow suit as this week goes by.

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Supergirl season 3 returns with "Legion of Superheroes" on Monday, January 15th @ 8pm ET on The CW.

Source: The CW