In the context of improvement works of security conditions in the Armand Trousseau hospital (Paul-Louis Chigot building), our project proposal was to create 3 outdoor staircases that would help evacuating people in emergency cases. The staircases are designed like thin and shiny towers hugging this hospital for sick children in a singular way. The metallic and articulated triangular panels are revealed when hit by sunrays. The many surfaces are folded like a sleek piece of paper. The stairs and safety guards can be seen through the almost-transparent cladding.