"Evil", sometimes listed as "Evil (Is Going On)", is a Chicago blues standard written by Willie Dixon. Howlin' Wolf recorded the song for Chess Records in 1954. It was included on the 1959 compilation album Moanin' in the Moonlight. When he re-recorded it for The Howlin' Wolf Album in 1969, "Evil" became Wolf's last charting single (#43 Billboard R&B chart).