New to me, but not the internet, Wikipedia explains:
The Cross and the Switchblade is a book written in 1963 by pastor David Wilkerson with John and Elizabeth Sherrill. It tells the true story of Wilkerson's first five years in New York City, where he ministered to disillusioned youth, encouraging them to turn away from the drugs and gang violence they were involved with. The book became a best seller, with more than 15 million copies distributed in over 30 languages.It was later turned into a movie and comic book. There are several copies on sale at eBay. Via.