Rumour mills suggest that Ranbir Kapoor will be shaking a leg with Sanjay Dutt for Sanju

Filmmaker Vidhu Vinod Chopra says that he, along with writer Abhijaat Joshi, is working on the script of "Marco" -- which will be actor Sanjay Dutt's comeback movie -- and that the project will go on the floors in the first half of next year.