Primarily known for his vocal contribution to "Rudeboy" -- a late-2013 hit single from U.K. drum'n'bass duo, Sigma -- the South London-based rapper and singer, Doctor, initially built his reputation by working with luminaries of the grime scene. His 2005 mixtape, Before Surgery, featured production from Soundbwoy on "Never Wanna Say," a track that would go on to provide additional exposure for Doctor when it was issued the following year as a single. Prestigious appearances at the Sidewinder club night -- an event that gave exposure to artists such as Wiley and Wretch 32 -- also helped to raise his profile. Following recording collaborations with NY and Ironik, an even bigger break came in 2010 when the long-established production duo, Chase & Status, worked with him on the single "Tek Your Time." As a result, more requests for vocal assistance came his way, and a plethora of videos subsequently flooded YouTube in the early part of the new decade, with Doctor featured alongside Bearman, Stenchman, and DJ Squarewave, among others. With "Rudeboy" -- the Sigma collaboration -- charting in the last days of 2013, the effects of its BBC 1Xtra playlisting continued to benefit both artists at the beginning of 2014. ~ James Wilkinson