Today's interest in the supernatural often seems to put the emphasis on demons, ghosts and other evil powers. But what about the forces of good? Angels are thought by some to be purely the province of song lyrics, fairy tales and popular mythology, yet they are mentioned nearly 300 times in the Bible and are infact a very real source of comfort and strength for many people today. Billy Graham writes that this has been 'one of the most fascinating studies of my life', and in it he looks at what angels are and the roles that they can play. 'In a materialistic world which nevertheless is riddled with evil and suffering,' he writes, 'we need to discover afresh the Bible's teaching about angels. . .I believe the subject is more relevant today than perhaps at any time in history.'