This week, The CW's Supergirl heads into an unprecedented nine-week hiatus. Starting tonight, DC's Legends of Tomorrow will occupy Supergirl's usual Monday time slot until April 9, only for Supergirl to return on April 16.

Supergirl will go on hiatus following a promise from CW President Mark Pedowitz that the network won’t air any more than four superhero shows at one time. In all, The CW boasts five DCTV shows: Arrow, The Flash, Legends of Tomorrow, Supergirl and Black Lightning. Black Lightning is a new addition to The CW's roster, premiering just last month. To make room for the freshman series, The CW shuffled its DCTV shows so that Legends of Tomorrow and Supergirl will share the 8 pm time slot on Mondays, while Black Lightning cinches Legends of Tomorrow's former Tuesday night spot.

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The CW announced the change back in December, shortly after Supergirl's midseason finale. Supergirl fans didn't take too kindly to the news, launching a petition to restore the series to its proper time slot to finish out its run. The petition, which boasts over 5,000 signatures at the time of writing, cited concerns for the show's ratings: "It will tarnish the shows viewer ratings as it will be off for over two months and a lot of people will wonder if the show has been cancelled or moved elsewhere."

Fortunately for Supergirl fans, Legends of Tomorrow typically runs a short season; this year, Legends will cap off at episode 18. Supergirl, on the other hand, will air a full 23 episodes. The Supergirl Season 3 finale is expected to air on Monday, June 18.

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Prior to this nine-week break, Supergirl returned from its winter hiatus with four episodes, running January 15 through February 5. This handful of episodes introduced Legionnaire Brianiac-5 and sent the Legion of Super-Heroes into action for the first time this season. However, it wasn't a walk in the park for the Girl of Steel, who ultimately discovered a second Worldkiller named Purity and a vital truth: that a Worldkiller’s personality overtakes their humanity.

When Supergirl returns, the show will explore the ramifications of this realization. After all, if Purity has a human side, then Reign must as well; Kara just hasn't yet realized how close to home these Worldkillers have really come. So, when Season 3 continues, the Girl of Steel will be forced to confront villains that don't know they're villains. Unlike Kara, Lena Luthor has realized that her friend Sam Arias is Reign, so the show also seems to be building a conflict between Kara, Alex and their friends.

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What's more, Supergirl has left dangling an important question about the Legion of Super-Heroes. In the last episode before the break, Saturn Girl revealed she and Brainiac-5 had a secret mission they hadn’t shared with Mon-El. Unfortunately, fans will have to wait out the nine-week hiatus to find out what exactly that is.

Returning Monday, April 16 at 8 p.m. 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.