There's a witty, stencil-based street artist from Bristol who has been getting up all over American cities. Perhaps you've heard of him? Since 1992, Nick Walker has been combining freehand and stencil graffiti to explore issues in politics and religion. With his “Vandal” character, Walker plays with notions of perception, and his well-dressed gentleman stencil is artsy enough that it often goes unnoticed as illegal street painting. Like his more famous counterpart, Banksy, Walker balances a healthy dose of humor and a strong sense of composition to engage audiences on contemporary issues. This makes him one of the most successful street-to-gallery artists around—and also why, two years ago, The Independent declared, “Move over Banksy!” after Walker sold out shows in both L.A. and London. Tomorrow, we'll have images of Walker's latest show in London, but for now get polished up on this guy's work by taking a look at some of his street pieces.