Today during its Nintendo Direct conference, the company announced that Mario & Luigi: Dream Team is coming on August 11, fulfilling its previous summer window. The presentation also showed the game in action, and explained a bit of the story.
The game takes place on a mysterious new island where the gang is visiting. Princess Peach is kidnapped, as she is wont to do, and pulled into a dream world. When Luigi sleeps on a special kind of pillow, he opens a path to the dream world that Mario can use to look around. The footage also showed a variety of attacks and navigation, including tilting the 3DS to aim and pulling on Luigi's mustache in the real world to launch Mario in a slingshot motion in the dream world.