Mario & Luigi: Bowser's Inside Story is a role-playing video game, developed by AlphaDream and published by Nintendo for the Nintendo DS handheld game console in 2009. It is the third game in the Mario & Luigi role-playing series, and it made use of the interactive screens of the DS in some of its gameplay mechanics while also introducing several elements that would be used in the series' future gameplay.
The game's plot involves Mario and Luigi being inhaled into the body of their long-time nemesis, Bowser. The Mario brothers learn to help Bowser, who is unaware of their presence, to combat their mutual enemy Fawful, who has taken control of the Mushroom Kingdom. The gameplay focuses on the cooperation of the trio, who use their specific abilities to solve puzzles, fight enemies and thus progress through the game. Similar to its predecessors, its role-playing style emphasizes a turn-based battle system focused on timing accuracy, and it is almost entirely comedic in nature.
The game was both critically and commercially successful, with many fans and critics considering it to be the best game in the series. It is the second best-selling Mario role-playing game, having sold over four million copies worldwide by April 2011.
A sequel, titled Mario & Luigi: Dream Team, was released for the Nintendo 3DS on July 12, 2013. A remake for the Nintendo 3DS, titled Mario & Luigi: Bowser's Inside Story + Bowser Jr.'s Journey, was released in Japan on December 27, 2018, in North America on January 11, 2019, in Europe on January 25, 2019, and in Australia on January 26, 2019.
