Pakistan, March 20 -- Singer Nupur Sanon on Thursday unveiled her unplugged version of B Praak's hit track "Filhall" in her voice and superstar Akshay Kumar has made a special appearance in the latest cover. Last year, Akshay and Nupur appeared in the music video of "Filhall", which crossed over 500 million views on YouTube. The video featured Akshay as a Punjabi man in love with Nupur's character and narrates how their love story had a tragic end. Sharing a link of the unplugged version, Nupur took to Instagram and wrote: "From making YouTube covers of Bollywood songs just for fun to finally making a cover of my own song..the feeling is nothing but surreal! "Watch till the end for a sweet SURPRISE!! @akshaykumar. Have put my heart and so...