While the last game in the Mario And Luigi series had you playing inside Bowser's belly, this one takes place in Luigi's dreams where he's a brave hero. Luigi's dreams must be pretty odd as they involve over 30 Luigi characters propping up Mario! Apparently this is one of the major themes of Mario and Luigi: Dream Team.
In an interview with Rolling Stone, Miyamoto said: "It's almost a coincidence that this is coming out the same year as a Pikmin game, because one of the main themes of the Mario and Luigi: Dream Team is the idea of these mobs of Luigis - these big mobs of Luigis that are attacking the enemies that has sort of a Pikmin-like feel to it."
The Mario And Luigi: Dream Team release date has been set for summer 2013.