The film is based on a true story in London in the 1930s. If all goes as per plan, it will be written, produced and directed by Rai, who is planning to shoot with a Hollywood crew and cast.
Rai, who is half way through the script, has even found a working producer in the US associated with a major production house.
The director of the popular multi-starrer "Tridev", however, is not ready to give out the details at the moment.
"I am not willing to talk about the project yet since I will be sure of it only in October. Any Hollywood film has to go through several steps from the inception, to the script, casting and the final shooting," he says.
"The script is likely to take a few more months after which I will have to get a nod from my Hollywood-based working producer."
According to Rai, Shabbir Boxwalla - his Dubai-based financier friend and former associate - prodded him into going ahead with the project when he discussed the idea.
"My financier friend felt the subject was ideal for a film with an entire Hollywood cast and crew," Rai says.
The US-based Rai then contacted an American producer friend and gave her a hearing of the rough script. "She immensely liked the story and found me to be a fantastic hi-end writer," recalls Rai.
Rai plans to approach her in September once the script is ready. "If we are both convinced and I get a go-ahead, we'll begin selecting the actors through a casting agency," he says.
Asked if he was trying Hollywood because his last two Bollywood films, especially "Asambhav", did not do well, Rai says: "The project has nothing to do with the performance of my last two films though I must admit that I was a little bored working in Bollywood."
"The Hollywood project coincidentally happened when I was doing some serious introspection and looking for a change."
"Asambhav", he feels, was "far too ahead of its time". "I experimented with the technique on purpose knowing the possible consequences and the flak it could get if the film failed. I have no regrets on that count," Rai says.
"Bollywood is a little shy of technique, and foreign films allow you to go all out for technique. The industry is at the crossroads with makers undecided on whether they are looking for change," he says, hastening to add that he is in no way disillusioned with Bollywood.
"My disillusionment is with myself that the last few years haven't been very inspiring creatively. I am looking at the Hollywood film as a breakthrough that will give me a refreshing change," he says.
The last Hollywood film that impressed Rai was "Lord of the Rings III" that he remembers watching in Los Angeles. "I had not even seen the previous two parts at that time. The film was probably the best in terms of imagination," he recalls.