The Matrix Online was a massively multiplayer online role-playing game (MMORPG) developed by Monolith Productions. It was the official continuation of the storyline of the The Matrix series of films. The game began closed beta-testing in June 2004 which was then opened for people who pre-ordered the game in November 2004. Warner Bros. and Sega officially released MxO on March 22, 2005 in the United States. It was released in Europe on April 15, 2005. The game ran continuously from then until it was shut down on July 31, 2009 by Sony Online Entertainment.