Gran Turismo creator Kazunori Yamauchi has a surprising cameo in the movie

polygon.com:

There are few video game creatives as tireless in their pursuit of perfection as Kazunori Yamauchi. The head of the Polyphony Digital studio, and creator of Gran Turismo, is a motoring obsessive whose project for the last 25 years has been to build an interactive temple to cars and motorsport. He lives and breathes this quest. Between 2009 and 2016, he raced GT cars in 24-hour races, then gave the development team notes on exactly how it should look when the sun comes up over the Nordschleife Nürburgring.

There’s something of a mythology around Yamauchi (or, as many GT fans call him, Kaz), and I went into the Gran Turismomovie expecting him to make an appearance as himself, perhaps stepping out of one of his beloved Nissan GT-R cars in racing overalls. To my total delight, the very first shot of the film was of Kaz — fully suited up, of course — kneeling on a racing circuit’s asphalt, carefully studying the camber of a turn. But here’s the twist: It isn’t Yamauchi. It’s an actor portraying him.

Yamauchi doesn’t play a huge role in the film, which tells (with a good degree of creative license) the true story of Jann Mardenborough, a Gran Turismo player who graduated from the GT Academy program to a career as a professional racing driver. Aside from the nakedly promotional opening montage that establishes the brilliance and perfectionism of Polyphony and the Gran Turismo games, Yamauchi (the character) mostly appears in the background of press launches and other notable moments in Mardenborough’s career, looking on approvingly (as far as you can tell from his stoic countenance). He only has one line, and he’s mostly called on to provide reaction shots in which he doesn’t react very much. But he hangs around quite a bit,