Sampson first shot to fame in 2008 after winning the second series of Britain's Got Talent at the tender age of 14. He had previously auditioned for the first series but failed to make it to the live semi-finals. Three years after winning Britain's Got Talent, Sampson got his first acting role after joining the cast of BBC school drama Waterloo Road and appearing in 30 episodes between 2011 and 2013. He has also appeared in Mount Pleasant, Casualty, The Dumping Ground and movies Street Dance 3D and Street Dance 2 as well as presenting Friday Download.
Sampson is an ambassador for United Dance Organisation. He suffers from Scheuermann's disease which affects the way bones develop in children, although he is adamant he could never give up dancing.