New York, June 30 : Film director Jonathan Levine says that he had to teach Sir Ben Kingsley how to smoke cannabis for the latter’s role in his film ‘The Wackness’, though using a fake joint.

"I had to teach him how to properly hit a bong," the New York Daily News quoted the writer/director as saying at the Cinema Society screening of the movie.

The film is dark comedy about dealing pot in New York in the ‘90s, and it depicts Kingsley as a pothead therapist.