Everyone associated with the film and all members of the cast and crew who attend the shooting regularly have signed a written contract swearing utter secrecy.
So protective and apprehensive are they about breach of confidentiality that the primary members of the cast have gone almost underground.
"If you thought Yashraj Films are protective about the details regarding their films, then you've to see what levels of secrecy are being exercized for Fashion.
All of us are virtually on tenterhooks trying to keep the characters, scenes and situations under wraps. But the more we try the more it seems people outside are trying to know what we're up to," says a very prominent part of the Fashion team.
Earlier this week when Neil Mathur dropped in to meet Madhur on the sets of Fashion there was widespread speculation that Neil has been signed for a role in the film.
In fact the actor had dropped in for a casual chat. Neil confirms he hasn't met Madhur for any particular film.
Reluctant to speak Madhur finally says, "We're all getting worried about the constant attention being given to Fashion. I admit it's the most glamorous film I've made. But I still find the curiosity about what we're doing to be a little unhealthy and scary."
The last straw was the reporting of Kangana Ranaut's wardrobe-malfunction sequence last week. The actress who's currently completely immersed in her role, freaked out when the news of the scene was reported the morning after it was shot.
Security is further being tightened on the sets of Fashion, as there's a prevalent fear on the sets that someone or some people are planning a quickie to beat Fashion to the theatres.
Sighs Madhur, "We can't understand how our scenes are leaking out. The security is so tight even I am frisked every morning before entering the sets. We aren't insecure about others making fashion-related films.
I'll shoot at my own pace and wrap up the film by May. But the curiosity about what I'm making is more alarming than flattering."