Prior to Massive Attack, Vowles, along with Robert Delegate Naja, Grant Marshall, Nellee Hooper, Adrian Thaws and others were the Wild Bunch crew, named after the western film of the same name by Sam Peckinpah. Interviews with band members have pointed to differences of opinion in the creative direction the band should go. Vowles" nickname "Mushroom" comes from the arcade game, Centipede.
The game was installed at Special K"s Cafe, a popular hang-out spot in the mid-1980s for Vowles and his Wild Bunch peers.
Several members of The Wild Bunch formed Massive Attack. Vowles remained a member of Massive Attack until shortly after the release of their third full-length album, Mezzanine, in 1998.