Ranbir Kapoor's interest in the exotic beauty Nargis Fakhri is more professional than personal.

The US-born half-Pakistani half-Czech debutante's Hindi needs a lot of work, to put it mildly, and Kapoor has taken up the cause to perfect her language skills. Along with director Imtiaz Ali, Kapoor has been relentlessly working on Fakhri's diction.

In fact, sources say the entire Rockstar team is determined to turn Fakhri desi before the final print of Rockstar is ready for release in September. All members of the crew have been advised to converse in Hindi with Fakhri; no one talks to her in English anymore.

Ali and Kapoor had put aside the leading lady's linguistic problem at the start of the shoot. Ali was reportedly dazzled by her screen presence, and decided to sort out the tiny issue of language later. Now, with Rockstar nearly complete, the director and the lead actor have joined forces to make Fakhri's Hindi sound credible.

The two have two options -- either her lines can be dubbed by a professional dubbing artist, like Katrina Kaif's lines were in her first few films, or Fakhri improves her Hindi enough to sound convincing as a desi girl in time for the final print.

"Nargis' screen presence and her acting abilities are topnotch. Everyone from the unit is raving about her. But the matter of her lines still need to be sorted out, " said a source.

Ali and Kapoor have reportedly taken the tougher route and are working on Fakhri's Hindi round the clock. The 5'9" tall Fakhri was featured in the 2009 Kingfisher calendar. She has also done television commercials for Herbal Essence, Pantene, and Ponds in the US.