Every summer has its sleepers. Last year the surprise box office hits included the heist thriller Now You See Me, the comedy We're the Millers and Woody Allen's drama Blue Jasmine. In 2012 the unexpected biggies were the rude comedy Ted and the male-stripper romp Magic Mike.

Chef

This summer, the biggest surprise has been a scruffly little comedy-drama about a food truck. Made by A-list filmmakers and actors, Chef opened in America on May 9th and began its climb up the box office chart, entering the top 10 on the following weekend and remaining there for more than six weeks. And while plenty of big movies have made more money (Chef has earned $21m, a tenth of the latest X-men's box office receipts), none has managed such longevity at the top.

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It's not like Chef's cast and crew are newcomers to success. Pretty much everyone involved in the film has had blockbuster attention in the past, especially as the film sees writer-director-star Jon Favreau reunited with his Iron Man cohorts Robert Downey Jr and Scarlett Johansson, plus top TV star Sofia Vergara, John Leguizamo (Ice Age), Bobby Cannavale (Blue Jasmine), Oliver Platt (X-men: First Class) and double Oscar-winner Dustin Hoffman.

Chef's appeal is that it's clearly a labour of love: the film is a refreshing antidote to formulaic Hollywood heavy-hitters that are crowding out the multiplexes. It's warm, funny and looks utterly delicious. And now it's ready to charm the world. Indeed, Chef opened across Europe last weekend, and landed at No 5 on the UK and Ireland box office chart.

Watch the trailer for 'Chef'