 In September 2015, he released a final instalment to his "WickedSkengMan" freestyle series, "WickedSkengMan 4", onto iTunes, along with a studio version of his "Shut Up" freestyle over XTC's "Functions on the Low" instrumental.The track debuted at number 18 on the UK chart dated 24 September, becoming Stormzy's first top 40 hit and the first ever freestyle to reach the top 40 in the United Kingdom.On 12 December 2015, Stormzy performed "Shut Up" during British heavyweight boxer Anthony Joshua's ring-walk for his fight versus Dillian Whyte.