Who Plays Young Vin Diesel and John Cena in the 'F9' Flashbacks?
No digital de-aging going on here in fleshing out the brothers' rivalry.

The speed-obsessed Fast and Furious franchise, which now includes 10 movies with the recent release of the long-delayed F9, has always glorified NOS-guzzling cars, purring engines, and physics-defying acts of vehicular destruction. As Vin Diesel's gearhead-turned-super-spy Dominic Toretto says in the first film, "I live my life a quarter mile at a time." But F9, in between its ridiculous stunts and its wild character resurrections, also spends a lot of time looking in the rearview mirror.
Specifically, F9 is the first Fast and Furious film to go all-in on flashbacks, opening with a scene from young Dom's life that's connected to his backstory as established way back in the beginning of the series. In interviews, director Justin Lin, returning to the series after departing with Fast and Furious 6, has talked about attempting to "solidify some of the mythology." What does that mean exactly? At least in F9, that means exploring the origin of Dom's ongoing family drama.
To do that, F9 decided not to go the Irishman digital de-aging route, which a number of Marvel movies have also used, and instead, Lin cast young actors to play young Dom and his (previously unmentioned) brother Jakob, played by John Cena in the present-day scenes. Being asked to play the "young" version of a global action superstar, particularly one as distinct as the bald-headed, gravel-voiced Diesel, can be an intimidating task. For every River Phoenix in Indiana Jones and the Last Crusade, there are countless forgettable ones. So, let's take a closer look at the actors cast to fill the broad-shouldered T-shirts of the Toretto brothers.

Who plays young Dominic Toretto (Vin Diesel) in F9?
Young Dominic Toretto is played by New Zealand-born actor Vinnie Bennett, who had a small role in 2017's Ghost in the Shell and has also appeared in a number of New Zealand television series (The Gulf, Good Grief, The Bad Seed).The 28-year-old actor doesn't exactly sound like or physically resemble the Dom we met back in 2001's The Fast and the Furious. (Diesel was in his early 30s when that film was shot.) But, in the F9 flashbacks that sketch out Dom's past, Bennett brings a Toretto-like intensity to the role, selling the anguish and pain of his father's death in a racing accident.
In a red carpet interview, Bennett explained that he didn't really get a chance to spend time with the cast because most of his scenes were shot separately towards the end of the production. The actor who plays "Younger Dom" at age 10 in another flashback/quasi-dream sequence probably got more face-time with the cast. Why is that? Ten-year-old Dom is played by Diesel's 10-year-old son, Vincent Sinclair. On the Tonight Show, proud papa Diesel told Jimmy Fallon that casting his son was director Justin Lin's idea. If you're a Dom completist, it's also worth noting that Furious 7 also included a "Young Dom," but the role was played by child actor Alex McGee.

Who plays young Jakob Toretto (John Cena) in F9?
Young Jakob is played by English actor Finn Cole, who you might recognize from his roles on the BBC's historical drama Peaky Blinders and TNT's family crime drama Animal Kingdom. Does he look like square-jawed muscle man John Cena? Not exactly, but, again, not many people look like John Cena. As the less-important-to-the-plot Toretto brother, he doesn't make as much of an impression as Bennett, but he helps make sense of Jakob and Dom's convoluted backstory.
Jakob will likely get folded into the main crew, a requirement of many villains in the series, and we could potentially see more of Cole as the franchise attempts to untangle its increasingly byzantine plot. In an interview with Vulture, Diesel noted that the movies will continue to explore Dom's lineage. "I think there is an inevitable moment when you are going to meet my father’s mother," he explained. Luckily, Dom remembers everything about his father, so there should be plenty of stories to tell.