An internet based project that combines web, documentary, smart-phone apps, online social gaming and interactivity hosted by a cross- media platform where you can find, face and fix a big city’s errors. The project has two core parts: 1/A web short-documentary series on the errors of a city called “Life in a city full of errors” that aims to attract people’s attention to the problems that destroy the city, to awaken public response, to advertise the platform through mass media coverage and to create an active audience that will participate in the second part of the project which is 2/ an online game called “Life in a city full of (T)errors” in which users create a personal online profile to participate. The game, whose online environment is an interactive, playful comics- like map of the city, works as follows: the gamers go out and film an error of their city AND their reaction to that error with the use of their mobile phone; they make a one 1-minute video about it; they upload it on our map with the use of a smart-phone app; and that way they create colored points, gather points, win prizes and learn that they do have a say on how they want and need their city to be. City of Errors is a platform that can be applied to any big city in the world simply by adjusting its content.