Hideyuki Nagai is a young Japanese artist, born in 1991. We’re pretty sure you’ll find his work just unbelievable, even if you are not much into art. Just take a look at these 3D optical illusion sketches. What is great is that they’re not just on a single surface, but they expand on 2, creating a sort of environment coming from just 2 pieces of paper. The work is mainly made with just pencil on paper.