Mumbai: Shah Rukh Khan and Katrina Kaif have been busy shooting for their upcoming release ‘Zero’.

The two, who have already worked together in ‘Jab Tak Hai Jaan’, were recently filming for a song at suburban Studios in Mumbai.

A source told DNA, “A special sari look for Katrina was designed for this song. In the film, she plays an actress who is dealing with life post a terrible break-up and becomes a chronic alcoholic, whereas Shah Rukh plays a midget who is besotted by her.”

The actress reportedly left for her hometown London to reunite with her family soon after the shoot.

Directed by Aanand L. Rai, ‘Zero’, also starring Anushka Sharma, is slated for a Christmas release.