It's all about the plumbers Mario and Luigi who have to fight of abdominal creatures crawling out of New York's sewers. The game was well received and has evolved considerably over time. The sequel called Super Mario Bros. came out in 1985 as a two player game for Nintendo gaming consoles. It remained one of the best selling video games of all time until it was outsold by Wii Sports, a sports game (and another Nintendo marketing masterpiece) for this increasing number of people who want peace of mind without actually doing sports.
Anyways, may I now present you the next generation of the game: Super Fusion Mario Bros.
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The boys did an awesome dance show at FUSION of York 2011, a charity fashion & dance performance that takes place every year around March time. I quite like the event as it is always an excellent excuse for taking pictures as you can see here.
For the keen folks, here are some more sources of information about the bros.
Mario Bros. at Nintendo.
Mario Bros. on Wikipedia.
Super Mario Bros. on Wikipedia.
Super Fusion Mario Bros. at York.