Producer Jayantilal Gada confirmed, while Bachchan is being sought to star in the Hindi part, Mohanlal is in talks to feature in the south version.
"We have approached them but they are yet to sign on the dotted lines. We have narrated the story to them and they both have given positive feedback. For the south version, we have Mr Mohanlal and for Hindi part, we have Mr Bachchan," Gada told PTI.
The producer added the forthcoming film is not a remake of the 1965 superhit suspense movie "Gumnaam", featuring Manoj Kumar and Nanda in the lead.
Director E Niwas, whose last release was "Total Siyapaa", is helming the film.
The film will be shot on an island in Mauritius and will go in floors soon.
The makers are aiming for a theatrical release next year.