The 100 can be many things, from Battlestar Galactica to LOST, but musical is rarely one of them. Before all-out Grounder war erupts anew in Season 3, enjoy one of the peaceful moments in our first clip from the premiere, curiously featuring singer-songwriter Shawn Mendes.

Sans any real context, fans of the CW sci-fi series might not know what to make of a very musical moment from Season 3 premiere “Wanheda: Part 1,” but who among the sky people couldn’t use some decent tunes? After all, any music stored in Mount Weather … well, let’s just say it isn’t a terribly happy place anymore.

So reads the Season 3 synopsis for “Wanheda”:

SHAWN MENDES (SINGER-SONGWRITER SENSATION) GUEST STARS

Three months have passed since the tragedy at Mount Weather and our heroes learn that a bounty has been put on Clarke’s (Eliza Taylor) head. Unbeknownst to Clarke, a team led by Bellamy (Bob Morley) and Kane (Henry Ian Cusick) journeys deep into Grounder territory to save her. Meanwhile, Murphy (Richard Harmon) finds his way to the mansion and discovers a very different Jaha (Isaiah Washington) on a very different mission. Paige Turco, Devon Bostick, Marie Avgeropoulos, Lindsey Morgan, Ricky Whittle and Christopher Larkin also star.

In addition to is epic first trailer and poster, guest stars for The 100 Season 3 will include Black Sails star Zach McGowan as a rogue Grounder warrior named Roan, along with Sons of Anarchy alum Michael Beach as a new member of the Ark, and Brenda Strong as the leader of the mysterious Ice Nation.

The 100 Season 3 will premiere on January 21, behind the series premiere of Legends of Tomorrow, so check out the photos and trailers again below, and find out why the series is on our Best TV shows of 2015!

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