Bagwell was born in Preston, England, and studied art at Leeds Polytechnic.
His early career as a comics artist saw him write and draw his own strip, Syd Serene, for Deadline in 1988.
He also illustrated Black Axe (1993) for Marvel UK, a Nick Fury strip for Marvel Comics Presents, a Judge Dredd story for 2000 AD, and stories for Crisis and other titles, before moving on to develop concept art and digital design for computer games and film companies.
His work for that comic was noticed by Matt Smith, the editor of 2000 AD, who asked him to work on some one-off stories and then on new series Cradlegrave (2009).
Other stories Bagwell illustrated for 2000 AD include Indigo Prime, The Ten-Seconders and Tharg's Future Shocks.