Songs are integral part of Hindi films or movies produced in Mumbai. But some songs, especially item numbers, cost huge money, so much so that the amount could easily finance a regional film. ‘Party all night’ is such a song from Akshay Kumar-starrer Boss. It cost producers Rs 6 crore (approx). This big hit dance number, sang by famous rapper Yo Yo Honey Singh, saw Sonakshi Sinha shaking a leg with Akshay Kumar in the film. Over 600 foreign models were hired as background dancers for the song choreographed by Sumit Dutt (of Character Dheela fame) and Raju Khan. Till date, this song is said to be the most expensive song shot in Bollywood.