Ninja Theory is a British video game developer based in Cambridge, England.

The studio was founded in March 2000 by Tameem Anoniades, Nina Kristen, and Mike Ball as Just Add Monsters. Shortly afterwards, it was acquired by Argonaut Games. In 2004, the studio purchased itself form Argonaut Games and reformed as Ninja Theory. Between 2004 and 2018, the studio developed and released several titles such as Heavenly Sword, DmC: Devil May Cry, Disney Infinity 3.0, and Hellblade: Senua's Sacrifice.

On June 10, 2018, it was announced that the studio had been acquired by Xbox Game Studios. On June 9, 2019, the studio announced a new game in development, Bleeding Edge.

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