Team Umbra rises - Friend or Foe?

There have been several disappearances all around Kanto, Johto, Hoen and Sinoh, and there are rumors about new organization residing in shadows. Will Ash be able to solve Team Umbra's mystery and rescue his captured friends? To his quest, he is joined by two "Nomad" Frontier Brains, Duel Duke Darren and Sagara the Diamond Emperor... (I do not own Pokemon, and story is from Gen. V)