The Beatles
Mohammed Emwazi, Aine Davis, Alexanda Kotey, and El Shafee Elsheikh were four London-raised men who traveled to join the ISIS. They became infamous for their presence in ISIS beheading videos, during which they killed at least 27 ISIS captives and are thought to have held and tortured many more. Some of their hostages dubbed these men "the Beatles" and gave each a nickname corresponding to their respective musical counterpart. However in 2015, Emwazi was killed in Raqqa, Syria and the three other men have been arrested and are standing trial for the crimes they committed on behalf of ISIS. An international manhunt began in August 2014 to track down the four men after they were featured in the beheading of journalist James Foley.