Following brief employment at a pound shop, Nazir, who had since settled in East London, began work at a fish stall at Queen's Market, Upton Park, where his employer instructed him to use a trader's call to attract customers. He soon composed the song "One Pound Fish": After passing customers uploaded videos of him performing his song onto YouTube, it became an internet smash and a viral video, and he was invited to perform the song on the television show The X Factor. The song was later covered by Alesha Dixon, Timbaland and Mindless Behavior. In 2018, Nazir confirmed via Twitter that the low-cost fish to which he was referring were mackerel.
Post ''X Factor''
In November 2012, Nazir was signed by Warner Music as a recording artist, and released a dance version of his market sales pitch. A video was also filmed which featured Bollywood-style dancers and an appearance from former weatherman Michael Fish. The song was in the running for securing the Christmas Number One for 2012 alongside X Factor winner James Arthur's release of his winning song "Impossible".
Return to Pakistan
Nazir had arrived in the United Kingdom on a student visa, but soon left his studies to work, contrary to the terms of his student visa, as a fishmonger. In December 2012, it was revealed that he had been ordered by the Home Office to leave the country as his visa had expired. He returned to Pakistan in December 2012. His management said he would return to the UK to promote his musical career with a new entry visa. It added that his departure to Pakistan was in part to appear on Pakistani national television as he had gained huge popularity in his own country after the song and that he would be able to see his family before returning to the United Kingdom. His agent, Samir Ahmed, said: "He will be returning to Pakistan and will be celebrating New Year with his family. His return to the UK is pending approval of a working visa. We fully expect him to return in the coming weeks". According to a 2016 article in the New Statesman, Nazir was declined a new visa to enter the UK because he violated the terms of his last visa by singing as a professional entertainer. A year after that he applied for another visa to try and appear in a film about his life, however it was also denied.