Scenes from the film Fast and Furious 7. Photo provided to China Daily

The seventh episode is the most sentimental, partly because of a real-life tragedy.

Paul Walker, another lead actor from the Fast and Furious franchise, was killed in a car accident in November 2013 in the middle of filming. Computer-generated imagery was used to complete Walker's unfinished scenes.

"This is the hardest film I've ever done, because I lost a brother," Diesel says.

A short tribute clip at the end of Fast and Furious 7 mixes together Walker's scenes in the previous Fast and Furious films. Brian O'Conner, Walker's character in the film, will be retired from future films.

However, when old roles unexpectedly end, new characters are introduced.

Apart from a Lykan Hypersport, one of the most expensive cars in the world ($3.4 million) appearing at a Beijing news conference last week, action star Jason Statham's appearance also created a stir among fans. Statham plays Deckard Shaw, the film's "baddie".

"I don't really see myself as a villain," says Statham, who usually plays masculine heroes in films. "(In the movie) I just take care of my family. I'm not interested in money.

"I just love the fact that the fans love the franchise so much," Statham adds, laughing. He says he should have joined Fast and Furious in its sixth episode but eventually chose to delay his appearance until the seventh.

It was Statham's second visit to Beijing after visiting the city to promote The Expendables 3 last year. Statham, a fan of Bruce Lee, also predicts there will be more cooperation with Chinese filmmakers. He says he has developed a good friendship with Hong Kong martial arts director Corey Yuen ever since they filmed The Transporter series.

"I'm trying to do something with them (Yuen's team) very soon in China," Statham says.

"We have a script now."

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