“Chalk and cheese”, “oil and water” and “Beauty and the Beast” were just some of the baffled reactions circulating among Japanese cinephiles when news broke that auteur Hirokazu Koreeda had cast A-lister Haruka Ayase and television comic Daigo Yamamoto as a couple in his latest sci-fi drama, Sheep in the Box.

Watching them enter one of the exclusive terraces of the Palais des Festivals et des Congres in Cannes, where Koreeda’s film debuted at the French resort city’s annual film festival last month, it is easy to understand the online commotion brought about by this curveball match-up.

Omnipresent on Japanese magazine covers and advertising billboards, Ayase arrives in a striped, multilayered designer outfit clearly unsuited for the heatwave sweeping across France. This does not concern Yamamoto, who turns up in a snappy T-shirt and trousers.

Ayase admits she was surprised when Koreeda, with whom she worked in 2015 for the family drama Our Little Sister, told her who her on-screen husband would be. “Daigo is a comedian,” she says. “And I think the director wanted to put me alongside him, and then…”

“In Japan, I think people do find us a very odd pairing,” interjects Yamamoto, who is well known at home for his appearances as one half – the goofy half, no less – of the network television comedy duo Chidori.

“It might have something to do with [Koreeda] playing on our differences,” he continues. “But when people actually watch the film, they will realise that we’re not such an odd pairing after all.”