Brett is the son of a dockyard worker and grew up in Portsmouth, England. When working on the stage crew at the Chichester Festival Theatre, and watching from the wings, the great Sir John Mills Brett decided he wanted to act and he applied for drama school. He attended the Guildhall School of Music and Drama in the Barbican, City of London - Where he was awarded their Gold Medal for acting. He began his professional career by returned again to Chichester, this time to perform in the repertory company, where his first job was an exciting nightly fight sequence with Sir Donald Sinden in 'The Scarlet Pimpernel', directed by Nicholas HytnerBrett has played diverse roles on stages all around England which has included the Royal National Theatre as Kevin in 'Single Spies' alongside Alan Bennett, Simon Callow and Prunella Scales; in 'Antony and Cleopatra' starring Alan Rickman,Helen Mirren and Samuel West; and as 'Eilif' opposite Diana Rigg and Lesley Sharp in 'Mother Courage'.Brett's first breakthrough in television came with the support of the legendary producer, Leonard Lewis, on the police series Rockliffe's Babies (1987) where he played the racist rookie detective Steve Hood. He has played guest and leading characters in many British television series.His first film role was a scene with Charlton Heston in L'isola del tesoro (1990) with Pete Postlethwaite and a young Christian Bale. His first major film role came with the part of Taktarov, a battle-worn Russian mercenary in the horror film Outpost (2008) starring alongside Ray Stevenson, Julian Wadham and Richard Brake. He played the hero fireman Paul in Lost Christmas (2011), opposite Jason Flemyng starring Eddie Izzard directed by John Hay and In the horror comedy feature film Kill Me Now (2012) Brett plays the lead 'Driller Killer', a serial killer who seeks revenge against the idleness of the American teenager. He stars alongside Michael Swaim' Kyle Mooney and Beck Bennett. Brett has since played roles ranging from a directors Agent "They'll take your body and soul - but they will pay for it" Untitled (A Film) (2017) opposite Mark Dymond to the Pedophile 'Bill Starling' in Six from Eight directed by Steve Crowhurst.