#BottleCapChallenge is the latest sensation ruling social media. Akshay Kumar, Vidyut Jammwal, Sushmita Sen, Tiger Shroff & many others performed the challenge. There were some like Kunal Kemmu and Sunil Grover who gave the whole thing a comical touch. The latest to join the list is Justin Bieber and Mariah Carey. While Bieber nails the challenge, Carey adds a completely new twist to the challenge.