Kuai and Yang kiss Lu at the press conference. Jiang Dong / China Daily

Chen also lifts the curtain on another highlight of the movie: the big-screen debut of Lu Han, a Beijing-born heartthrob to numerous teenagers.

"When I was picking the candidates for the grandson role in the movie, the young girls at 15 or 16 in my team all screamed to recommend Lu," Chen jokes. "The cries almost made me deaf."

The Venice Film Festival-nominated director may not be the only one witnessing the star power of Lu, 24, who made his first public appearance at the Miss Granny press conference since he filed a lawsuit to terminate his contract with SM Entertainment, the largest talent agency in South Korea, on Oct 10.

Kuai recalls that she could not even see Lu at first at the film set, as many enthusiastic fans blocked the way.

There was an echo of that memory at the press conference. More than 100 youngsters, with flowers tagged "fans from Spain and Indonesia", were waiting outside the conference hall. One fan even tried to break into the hall, where entry was restricted to the movie crew and reporters.

Kuai says that Lu is low-profile, modest and "very polite". "Every time he meets me with a 90-degree bow, so I have to salute him with the same gesture," she jokes.

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