http://www.imdb.com/title/tt5289986/?ref_=ttep_ep16

Whatever issues The 100 may have had this season, the series pulled out a pretty exciting finale that not only saw Lexa return and finally receive the heroic moment she was denied all those episodes ago, but it also wrapped up the A.L.I.E. storyline while setting the stage for a global, potentially unstoppable threat in Season 4. Each season the show has raised the stakes and expanded in scope through world-building, and this latest development will potentially expand The 100's lens to encompass the entire world. It's no longer just about the survival of the Hundred or Skaikru or the local Grounder population; the fate of humanity is in the hands of the few, as it usually tends to be in these situations